Is getting the specified P-Metric tires installed and selling the existing LT tires on Craigslist or something similar an option? Seems there is little upside other than saving a buck to trying to make the existing tires work.
wrong tires type :(
- Thread starter MetalSlug
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Originally Posted By: mrsilv04
You're always entitled to your own opinion, but you're not entitled to your own version of the facts.
You're missing the key fact yourself. That sticker you keep posting as gospel is the upper limit. It is what is required for the LT tire to achieve 100% of the load rating of the P-metric's (de-rated) load rating on the same vehicle.
If you are NOT running at full load, you can SAFELY run the LT tire at the door jamb rating, because the contact patch and sidewall flex at light load will be no worse than at full load and the full pressure.
I agree with what Rand posted. An LT tire in this application and at the door-jamb pressure can SAFELY be loaded to about 80% of the vehicle's capacity based on P-metric tires at that same pressure. To go to 100%, yes you need to raise the LT's pressure to higher than you would the P-metric, because the P-metric can handle the added sidewall flex and increased contact patch size. The LT tire can't.
What I'm saying is that CONVERSELY, running the LT tire lightly loaded at the pressure needed for FULL load results in an unnecessarily small and contact patch, with the resulting poor handling. I never said it was safe to run full load with LT tires at only 35 PSI.
You're always entitled to your own opinion, but you're not entitled to your own version of the facts.
You're missing the key fact yourself. That sticker you keep posting as gospel is the upper limit. It is what is required for the LT tire to achieve 100% of the load rating of the P-metric's (de-rated) load rating on the same vehicle.
If you are NOT running at full load, you can SAFELY run the LT tire at the door jamb rating, because the contact patch and sidewall flex at light load will be no worse than at full load and the full pressure.
I agree with what Rand posted. An LT tire in this application and at the door-jamb pressure can SAFELY be loaded to about 80% of the vehicle's capacity based on P-metric tires at that same pressure. To go to 100%, yes you need to raise the LT's pressure to higher than you would the P-metric, because the P-metric can handle the added sidewall flex and increased contact patch size. The LT tire can't.
What I'm saying is that CONVERSELY, running the LT tire lightly loaded at the pressure needed for FULL load results in an unnecessarily small and contact patch, with the resulting poor handling. I never said it was safe to run full load with LT tires at only 35 PSI.
The truck now has the right tires. The only reason for these trucks coming with CAR TIRES is so they ride nicer. I'll take a truck tire for truck use.
Originally Posted By: 440Magnum
Originally Posted By: mrsilv04
You're always entitled to your own opinion, but you're not entitled to your own version of the facts.
You're missing the key fact yourself. That sticker you keep posting as gospel is the upper limit. It is what is required for the LT tire to achieve 100% of the load rating of the P-metric's (de-rated) load rating on the same vehicle.
If you are NOT running at full load, you can SAFELY run the LT tire at the door jamb rating, because the contact patch and sidewall flex at light load will be no worse than at full load and the full pressure.
I agree with what Rand posted. An LT tire in this application and at the door-jamb pressure can SAFELY be loaded to about 80% of the vehicle's capacity based on P-metric tires at that same pressure. To go to 100%, yes you need to raise the LT's pressure to higher than you would the P-metric, because the P-metric can handle the added sidewall flex and increased contact patch size. The LT tire can't.
What I'm saying is that CONVERSELY, running the LT tire lightly loaded at the pressure needed for FULL load results in an unnecessarily small and contact patch, with the resulting poor handling. I never said it was safe to run full load with LT tires at only 35 PSI.
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
Originally Posted By: 440Magnum
Originally Posted By: mrsilv04
You're always entitled to your own opinion, but you're not entitled to your own version of the facts.
You're missing the key fact yourself. That sticker you keep posting as gospel is the upper limit. It is what is required for the LT tire to achieve 100% of the load rating of the P-metric's (de-rated) load rating on the same vehicle.
If you are NOT running at full load, you can SAFELY run the LT tire at the door jamb rating, because the contact patch and sidewall flex at light load will be no worse than at full load and the full pressure.
I agree with what Rand posted. An LT tire in this application and at the door-jamb pressure can SAFELY be loaded to about 80% of the vehicle's capacity based on P-metric tires at that same pressure. To go to 100%, yes you need to raise the LT's pressure to higher than you would the P-metric, because the P-metric can handle the added sidewall flex and increased contact patch size. The LT tire can't.
What I'm saying is that CONVERSELY, running the LT tire lightly loaded at the pressure needed for FULL load results in an unnecessarily small and contact patch, with the resulting poor handling. I never said it was safe to run full load with LT tires at only 35 PSI.
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
OVERKILL
$100 Site Donor 2021
Originally Posted By: Miller88
The truck now has the right tires.
No, it calls for P-Metric tires. Those are the RIGHT tires.
Originally Posted By: Miller88
The only reason for these trucks coming with CAR TIRES is so they ride nicer. I'll take a truck tire for truck use.
Define "truck use" with an Expedition? It doesn't have a bed, everything it is rated to do can be done with the stock-spec tires. When cross-shopping the Michelin LTX M/S 2 in 265/70/17 you are saying that he should run the LT265/70/17 at a lower load carrying capacity vs the stock spec P265/70/17 at the specified load capacity because somehow the LT version of the M/S 2 is more "manly" because it is a truck tire?
That reeks of truck nuts, STAAAAAACKSS!!! and "rolling coal". A thought process that really carries zero logic with it.
Originally Posted By: Miller88
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
This vehicle doesn't have a load chart for LT tires because it calls for P-Metric tires and its maximum capacities are all related to running THAT TIRE at its specified pressure. I'm not sure how degrading the vehicle's weight capacity just so it rides properly can be classified as "ideal"
Originally Posted By: Miller88
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
Your dad's F-350 could carrying your Cherokee in its bed and can probably tow three of them on a trailer. It has a capacity that requires Load Range E tires, so it spec's load range E tires. Your Cherokee does not specify Load Range E Tires, is not built to handle the weight to require those tires and the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
The truck now has the right tires.
No, it calls for P-Metric tires. Those are the RIGHT tires.
Originally Posted By: Miller88
The only reason for these trucks coming with CAR TIRES is so they ride nicer. I'll take a truck tire for truck use.
Define "truck use" with an Expedition? It doesn't have a bed, everything it is rated to do can be done with the stock-spec tires. When cross-shopping the Michelin LTX M/S 2 in 265/70/17 you are saying that he should run the LT265/70/17 at a lower load carrying capacity vs the stock spec P265/70/17 at the specified load capacity because somehow the LT version of the M/S 2 is more "manly" because it is a truck tire?
Originally Posted By: Miller88
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
This vehicle doesn't have a load chart for LT tires because it calls for P-Metric tires and its maximum capacities are all related to running THAT TIRE at its specified pressure. I'm not sure how degrading the vehicle's weight capacity just so it rides properly can be classified as "ideal"
Originally Posted By: Miller88
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
Your dad's F-350 could carrying your Cherokee in its bed and can probably tow three of them on a trailer. It has a capacity that requires Load Range E tires, so it spec's load range E tires. Your Cherokee does not specify Load Range E Tires, is not built to handle the weight to require those tires and the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
440Magnum - reread the warning. It says nothing about maximum capacity. It simply states that size for size, LT tires require higher pressures to carry the equivalent load. That's it.
Nobody here is saying to run 80 psi. And a Load Range E tire by its very nature has a much higher maximum capacity than a P-series tire. But to carry the same load as a P-series tire, it must be run at a higher pressure than the P-series tire to do so safely.
The other side of the arguement that the OP should run 35 psi on an LT tire is that he should be letting out air under most circumstances on the P-series tire, since he doesn't "need" the capacity. Does that sound right?
The OP does not need the full capacity of the Load Range E tires. But to have the same capacity as the OEM specified P-series tires, he needs to run a higher pressure than the P-series tire - Period.
Nobody here is saying to run 80 psi. And a Load Range E tire by its very nature has a much higher maximum capacity than a P-series tire. But to carry the same load as a P-series tire, it must be run at a higher pressure than the P-series tire to do so safely.
The other side of the arguement that the OP should run 35 psi on an LT tire is that he should be letting out air under most circumstances on the P-series tire, since he doesn't "need" the capacity. Does that sound right?
The OP does not need the full capacity of the Load Range E tires. But to have the same capacity as the OEM specified P-series tires, he needs to run a higher pressure than the P-series tire - Period.
The other thing to consider is the weight of the tire. If the LT tire is heavier than the specified p-metric tire, it puts more unsprung weight on the vehicle, possibly adversely impacting handling.
Not to mention liability. If there ever were an accident, you can bet lawyers will question LT tires installed on a vehicle where the placard indicates p-metric.
Not to mention liability. If there ever were an accident, you can bet lawyers will question LT tires installed on a vehicle where the placard indicates p-metric.
Originally Posted By: javacontour
The other thing to consider is the weight of the tire. If the LT tire is heavier than the specified p-metric tire, it puts more unsprung weight on the vehicle, possibly adversely impacting handling.
Not to mention liability. If there ever were an accident, you can bet lawyers will question LT tires installed on a vehicle where the placard indicates p-metric.
I doubt they would get anywhere.
If you were to go the other way, like we often see, then it would be a problem. There are a lot of ratty 1 ton trucks around here running around on P245/75-16 tires
The other thing to consider is the weight of the tire. If the LT tire is heavier than the specified p-metric tire, it puts more unsprung weight on the vehicle, possibly adversely impacting handling.
Not to mention liability. If there ever were an accident, you can bet lawyers will question LT tires installed on a vehicle where the placard indicates p-metric.
I doubt they would get anywhere.
If you were to go the other way, like we often see, then it would be a problem. There are a lot of ratty 1 ton trucks around here running around on P245/75-16 tires
Originally Posted By: OVERKILL
Originally Posted By: Miller88
The truck now has the right tires.
No, it calls for P-Metric tires. Those are the RIGHT tires.
Originally Posted By: Miller88
The only reason for these trucks coming with CAR TIRES is so they ride nicer. I'll take a truck tire for truck use.
Define "truck use" with an Expedition? It doesn't have a bed, everything it is rated to do can be done with the stock-spec tires. When cross-shopping the Michelin LTX M/S 2 in 265/70/17 you are saying that he should run the LT265/70/17 at a lower load carrying capacity vs the stock spec P265/70/17 at the specified load capacity because somehow the LT version of the M/S 2 is more "manly" because it is a truck tire?
That reeks of truck nuts, STAAAAAACKSS!!! and "rolling coal". A thought process that really carries zero logic with it.
Originally Posted By: Miller88
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
This vehicle doesn't have a load chart for LT tires because it calls for P-Metric tires and its maximum capacities are all related to running THAT TIRE at its specified pressure. I'm not sure how degrading the vehicle's weight capacity just so it rides properly can be classified as "ideal"
Originally Posted By: Miller88
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
Your dad's F-350 could carrying your Cherokee in its bed and can probably tow three of them on a trailer. It has a capacity that requires Load Range E tires, so it spec's load range E tires. Your Cherokee does not specify Load Range E Tires, is not built to handle the weight to require those tires and the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
If you feel safe loading a truck to it's GCWR with CAR TIRES good for you. If I owned a truck and used it as a truck, I'd be less concerned with it riding like a CAR and put real truck tires on it.
No one has ever made a mistake before ... you know ... like Ford telling people to deflate their tires to 26PSI because their truck based SUV rode like a truck.
Originally Posted By: Miller88
The truck now has the right tires.
No, it calls for P-Metric tires. Those are the RIGHT tires.
Originally Posted By: Miller88
The only reason for these trucks coming with CAR TIRES is so they ride nicer. I'll take a truck tire for truck use.
Define "truck use" with an Expedition? It doesn't have a bed, everything it is rated to do can be done with the stock-spec tires. When cross-shopping the Michelin LTX M/S 2 in 265/70/17 you are saying that he should run the LT265/70/17 at a lower load carrying capacity vs the stock spec P265/70/17 at the specified load capacity because somehow the LT version of the M/S 2 is more "manly" because it is a truck tire?
Originally Posted By: Miller88
You got it! Running the LT tire at recommended pressure for P-rated car tire will do no harm and is ideal. Now, if you're going to load the tire to it's capacity, then run it at the max.
This vehicle doesn't have a load chart for LT tires because it calls for P-Metric tires and its maximum capacities are all related to running THAT TIRE at its specified pressure. I'm not sure how degrading the vehicle's weight capacity just so it rides properly can be classified as "ideal"
Originally Posted By: Miller88
I run LT-E tires on my Cherokee. Usually inflate them to 30PSI. They wear evenly when the vehicle is aligned.
My dad's F350 comes with LT 265/75-16 tires ... because it's a truck. There is no pressure recommendations. Whenever it goes to the dealer, they inflate the tires to 80. Driving an unloaded 1 ton truck with 80PSI in the tires can get ... fun
Your dad's F-350 could carrying your Cherokee in its bed and can probably tow three of them on a trailer. It has a capacity that requires Load Range E tires, so it spec's load range E tires. Your Cherokee does not specify Load Range E Tires, is not built to handle the weight to require those tires and the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
If you feel safe loading a truck to it's GCWR with CAR TIRES good for you. If I owned a truck and used it as a truck, I'd be less concerned with it riding like a CAR and put real truck tires on it.
No one has ever made a mistake before ... you know ... like Ford telling people to deflate their tires to 26PSI because their truck based SUV rode like a truck.
The aversion to using P-series tires on light duty trucks (ie: 1/2 tons, compacts) is just silly. Load em up to the GCWR with P-series tires. That is what they were engineered and designed to do.
Personally, I can't wait to dump the LT series tires I've got on my F150 that the previous owner put on for the OEM P-series series.
Personally, I can't wait to dump the LT series tires I've got on my F150 that the previous owner put on for the OEM P-series series.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Miller88
If you feel safe loading a truck to it's GCWR with CAR TIRES good for you.
You honestly feel that the LTX M/S 2 in P-Metric is a "car tire". Tell me good sir, how many cars do you see fitted with that tire?
Quote:
If I owned a truck and used it as a truck, I'd be less concerned with it riding like a CAR and put real truck tires on it.
The OP has an Expedition, not a "truck". In fact my '02 Expedition, based on the F-150, is a heck of a lot more like a truck than his with 4 wheel independent suspension.
And it has nothing to do with ride. The vehicle's capacities are specified for the tires indicated on the placard. They are not LT tires.
Quote:
No one has ever made a mistake before ... you know ... like Ford telling people to deflate their tires to 26PSI because their truck based SUV rode like a truck.
Or some guy telling somebody to run LT tires on a vehicle that calls for P-Metrics at the P-Metric inflation pressure greatly decreasing their capacity either right?
If you feel safe loading a truck to it's GCWR with CAR TIRES good for you.
You honestly feel that the LTX M/S 2 in P-Metric is a "car tire". Tell me good sir, how many cars do you see fitted with that tire?
Quote:
If I owned a truck and used it as a truck, I'd be less concerned with it riding like a CAR and put real truck tires on it.
The OP has an Expedition, not a "truck". In fact my '02 Expedition, based on the F-150, is a heck of a lot more like a truck than his with 4 wheel independent suspension.
And it has nothing to do with ride. The vehicle's capacities are specified for the tires indicated on the placard. They are not LT tires.
Quote:
No one has ever made a mistake before ... you know ... like Ford telling people to deflate their tires to 26PSI because their truck based SUV rode like a truck.
Or some guy telling somebody to run LT tires on a vehicle that calls for P-Metrics at the P-Metric inflation pressure greatly decreasing their capacity either right?
Originally Posted By: OVERKILL
Originally Posted By: hattaresguy
35-40 psi is fine, if you inflate them to much the truck will ride like [censored].
I run the E's on my half ton at 40psi since day one and have never had any unusual wear or temperature increases.
If I was carrying a lot of weight on the highway like 1,500 in the bed I'd inflate them a bit more, that's where heat is generated. I'd probably run 60 in the rear.
If that is the factory spec for P-rated tires for your application you are running your tires potentially dangerously underinflated as you have reduced their load carrying capacity below stock spec for the vehicle.
See this document for details:
http://www.toyotires.ca/sites/default/files/loadinflationtable.pdf
Page 71 shows the following:
----------------------------
O.E. Information (Obtained from the T.I.P.):
Vehicle: 2006 Ford F-150 XLT 4X4 Super Crew Cab
Tire Size (Front/Rear): P255/70R17 110S Rim width = 7.5”
Inflation Pressure (Front/Rear) = 35 psi
Using the TRA Load Inflation Table (see Table 8), at the O.E. pressure of 35 psi, the P255/70R17 has a
load-carrying capacity of 2337 lbs. As this tire has been derated by the vehicle manufacturer by a factor
of 1.10 to account for its installation on a light truck, the actual load-carrying capacity is 2125 lbs.
After confirming that the O.E. rim width is within the allowable rim width range for LT265/70R17 121S
E/10, refer to the TRA LT Load Inflation Table. The ‘Single’ load values apply, and this tire requires an
inflation pressure of 45 psi (2255 lbs.) to maintain adequate load capacity.
----------------------------
At 35psi, the (larger width) LT tire above has a capacity of 235lbs less than the stock P-Metric tire. That is a reduction of 940lbs in carrying capacity for all four tires.
Now, for example, if I look up the stock tire size in the TRA chart shown later in the document, it shows a P265/70/17 LI 113 has a load capacity of 2,535lbs at 32psi. That is also what is shown when I look up the Michelin LTX MS/2 on TireRack. So, we reduce by a factor of 1.1 because it is a truck and we get a capacity of 2,304lbs.
I then scroll down to the LT section and look up the same size. LT265/70/17 has a capacity of 1,890lbs at 35psi. At 40PSI it is 2,070, at 45psi it is 2,255lbs and at 50psi we finally overtake the stock P-metric capacity and arrive at 2,470lbs.
So, using the derated P-Metric figure, the 4 stock tires give us a total weight carrying capacity of 4,608lbs per axle. Depending on how you are loaded will of course determine your distance from that figure. Using 35psi in the LT tire we reduce that capacity to 3,780lbs, a reduction of 828lbs of capacity per axle.
So my question to you is why are you running LT tires underinflated, reducing the load carrying capacity of the vehicle, rather than just running the correct P-Metric tire at stock pressure? (I am assuming your 1/2 ton doesn't call for something like a C-rated LT tire and rather a P-Metric) I found zero benefit from the LT tires on the Expedition, they were what the PO had put on and they were replaced with the correct tires. It isn't like with my F-250 where it actually called for LT tires and had the different loaded weights on the placard indicating what to run for pressure depending on what was in the bed. Your 1/2 ton truck doesn't have the carrying capacity to warrant an E-range tire, if it did, it would call for one. So either you are loading the vehicle up to levels it was not designed to carry, requiring a tire of that load range resulting in an unsafe vehicle or there is really no point in them being on there, which is why you are running them at the P-metric pressure, which, ironically, makes them a poorer choice in terms of carrying capacity than the stock P-Metric tires it calls for and is also potentially unsafe
If there's some compelling reason to running load range E tires on a vehicle that cannot utilize their capacity, please enlighten me.
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200. The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
Originally Posted By: hattaresguy
35-40 psi is fine, if you inflate them to much the truck will ride like [censored].
I run the E's on my half ton at 40psi since day one and have never had any unusual wear or temperature increases.
If I was carrying a lot of weight on the highway like 1,500 in the bed I'd inflate them a bit more, that's where heat is generated. I'd probably run 60 in the rear.
If that is the factory spec for P-rated tires for your application you are running your tires potentially dangerously underinflated as you have reduced their load carrying capacity below stock spec for the vehicle.
See this document for details:
http://www.toyotires.ca/sites/default/files/loadinflationtable.pdf
Page 71 shows the following:
----------------------------
O.E. Information (Obtained from the T.I.P.):
Vehicle: 2006 Ford F-150 XLT 4X4 Super Crew Cab
Tire Size (Front/Rear): P255/70R17 110S Rim width = 7.5”
Inflation Pressure (Front/Rear) = 35 psi
Using the TRA Load Inflation Table (see Table 8), at the O.E. pressure of 35 psi, the P255/70R17 has a
load-carrying capacity of 2337 lbs. As this tire has been derated by the vehicle manufacturer by a factor
of 1.10 to account for its installation on a light truck, the actual load-carrying capacity is 2125 lbs.
After confirming that the O.E. rim width is within the allowable rim width range for LT265/70R17 121S
E/10, refer to the TRA LT Load Inflation Table. The ‘Single’ load values apply, and this tire requires an
inflation pressure of 45 psi (2255 lbs.) to maintain adequate load capacity.
----------------------------
At 35psi, the (larger width) LT tire above has a capacity of 235lbs less than the stock P-Metric tire. That is a reduction of 940lbs in carrying capacity for all four tires.
Now, for example, if I look up the stock tire size in the TRA chart shown later in the document, it shows a P265/70/17 LI 113 has a load capacity of 2,535lbs at 32psi. That is also what is shown when I look up the Michelin LTX MS/2 on TireRack. So, we reduce by a factor of 1.1 because it is a truck and we get a capacity of 2,304lbs.
I then scroll down to the LT section and look up the same size. LT265/70/17 has a capacity of 1,890lbs at 35psi. At 40PSI it is 2,070, at 45psi it is 2,255lbs and at 50psi we finally overtake the stock P-metric capacity and arrive at 2,470lbs.
So, using the derated P-Metric figure, the 4 stock tires give us a total weight carrying capacity of 4,608lbs per axle. Depending on how you are loaded will of course determine your distance from that figure. Using 35psi in the LT tire we reduce that capacity to 3,780lbs, a reduction of 828lbs of capacity per axle.
So my question to you is why are you running LT tires underinflated, reducing the load carrying capacity of the vehicle, rather than just running the correct P-Metric tire at stock pressure? (I am assuming your 1/2 ton doesn't call for something like a C-rated LT tire and rather a P-Metric) I found zero benefit from the LT tires on the Expedition, they were what the PO had put on and they were replaced with the correct tires. It isn't like with my F-250 where it actually called for LT tires and had the different loaded weights on the placard indicating what to run for pressure depending on what was in the bed. Your 1/2 ton truck doesn't have the carrying capacity to warrant an E-range tire, if it did, it would call for one. So either you are loading the vehicle up to levels it was not designed to carry, requiring a tire of that load range resulting in an unsafe vehicle or there is really no point in them being on there, which is why you are running them at the P-metric pressure, which, ironically, makes them a poorer choice in terms of carrying capacity than the stock P-Metric tires it calls for and is also potentially unsafe
If there's some compelling reason to running load range E tires on a vehicle that cannot utilize their capacity, please enlighten me.
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200. The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
Last edited:
OVERKILL
$100 Site Donor 2021
Originally Posted By: hattaresguy
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
Did you have issues with the same tire in P-Metric regarding nails and screws or are you just being careful and figure the extra protection couldn't hurt?
Quote:
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200.
See my Expedition scales over 6K with just me in it and something like 1/4 tank (curb weight is supposed to be something like 5,500). The tire size I used in my example above is the tire size the Expedition takes.
Quote:
The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
But what is the vehicle spec'd for? What's your stock tire size?
Quote:
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
I don't think so really. I set my tires by the placard and can run the Expie empty or loaded to the gills with a trailer behind it and I know my tire pressure is appropriate for all of it. I think the guys over-thinking it are those trying to justify the use of an LT in a P-metric application and don't really have a legitimate reason for it. I mean your reason at least makes sense (the job site thing), but for a truck (and particularly an SUV) that sees dirt roads, maybe the trail into the cottage and the rest of it highway, unless you want to have "Man Tires" and run some aggressive tread pattern to show how awesome you are, I don't really see the point in reducing load carrying capacity and ride quality because for some reason an LT tire, because it has "truck" in the name, is more appropriate than potentially the exact same tire (like the LTX A/S or M/S) in P-Metric in the size on the placard.
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
Did you have issues with the same tire in P-Metric regarding nails and screws or are you just being careful and figure the extra protection couldn't hurt?
Quote:
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200.
See my Expedition scales over 6K with just me in it and something like 1/4 tank (curb weight is supposed to be something like 5,500). The tire size I used in my example above is the tire size the Expedition takes.
Quote:
The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
But what is the vehicle spec'd for? What's your stock tire size?
Quote:
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
I don't think so really. I set my tires by the placard and can run the Expie empty or loaded to the gills with a trailer behind it and I know my tire pressure is appropriate for all of it. I think the guys over-thinking it are those trying to justify the use of an LT in a P-metric application and don't really have a legitimate reason for it. I mean your reason at least makes sense (the job site thing), but for a truck (and particularly an SUV) that sees dirt roads, maybe the trail into the cottage and the rest of it highway, unless you want to have "Man Tires" and run some aggressive tread pattern to show how awesome you are, I don't really see the point in reducing load carrying capacity and ride quality because for some reason an LT tire, because it has "truck" in the name, is more appropriate than potentially the exact same tire (like the LTX A/S or M/S) in P-Metric in the size on the placard.
@hattaresguy the exp is about 6000lb with just a driver.. thats abit different application.
@miller88 I did say that. I didnt somehow say that its a good idea. I feel the OP should be running 45-50psi in a 6000lb suv
but 35psi totally empty shouldn't cause any immediate problems.
This also crosses over to recommending 29psi in a pmetric instead of 35psi "because you dont need the capacity" IMO not really a good idea.
I ran Dean 265/75R16's on my 2002 ranger they were
17/32 in LT, and 12.5/32 in P-metric.. Never had any real issues even going 80-90mph for 3-4 hours at a time.
Stock size was 245/75r16
I usually ran 36psi front and 32 rear but I would change it for load or offroad.
It was setup very heavy with welded rock sliders, a Milemarker 10500 on a 1/2" angle custom mount.
Never had any problems with the tires.. the shocks did like to go boom though.
I dont have the spec sheet in front of me.. but a typical tire such as a Cooper AT/3
is 16.5/32 or 17/32 in LT and flotation sizes
the same tire in p-metric sizes is 12.5/32 to 14/32
@miller88 I did say that. I didnt somehow say that its a good idea. I feel the OP should be running 45-50psi in a 6000lb suv
but 35psi totally empty shouldn't cause any immediate problems.
This also crosses over to recommending 29psi in a pmetric instead of 35psi "because you dont need the capacity" IMO not really a good idea.
I ran Dean 265/75R16's on my 2002 ranger they were
17/32 in LT, and 12.5/32 in P-metric.. Never had any real issues even going 80-90mph for 3-4 hours at a time.
Stock size was 245/75r16
I usually ran 36psi front and 32 rear but I would change it for load or offroad.
It was setup very heavy with welded rock sliders, a Milemarker 10500 on a 1/2" angle custom mount.
Never had any problems with the tires.. the shocks did like to go boom though.
I dont have the spec sheet in front of me.. but a typical tire such as a Cooper AT/3
is 16.5/32 or 17/32 in LT and flotation sizes
the same tire in p-metric sizes is 12.5/32 to 14/32
Last edited:
Originally Posted By: OVERKILL
Originally Posted By: hattaresguy
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
Did you have issues with the same tire in P-Metric regarding nails and screws or are you just being careful and figure the extra protection couldn't hurt?
Quote:
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200.
See my Expedition scales over 6K with just me in it and something like 1/4 tank (curb weight is supposed to be something like 5,500). The tire size I used in my example above is the tire size the Expedition takes.
Quote:
The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
But what is the vehicle spec'd for? What's your stock tire size?
Quote:
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
I don't think so really. I set my tires by the placard and can run the Expie empty or loaded to the gills with a trailer behind it and I know my tire pressure is appropriate for all of it. I think the guys over-thinking it are those trying to justify the use of an LT in a P-metric application and don't really have a legitimate reason for it. I mean your reason at least makes sense (the job site thing), but for a truck (and particularly an SUV) that sees dirt roads, maybe the trail into the cottage and the rest of it highway, unless you want to have "Man Tires" and run some aggressive tread pattern to show how awesome you are, I don't really see the point in reducing load carrying capacity and ride quality because for some reason an LT tire, because it has "truck" in the name, is more appropriate than potentially the exact same tire (like the LTX A/S or M/S) in P-Metric in the size on the placard.
I'm not going to continue arguing over P-Metric or LT tires - I'm not changing your opinion and you aren't going to change mine.
As for the sidewall thickness, I have seen that first hand off road (I'm sure sometimes that's similar to a job site).
A lot of people end up running pmetric 2 ply all terrains off road. Sure, the tread is aggressive, but the first twig or rock they come to, then end up trashing a sidewall.
I've been through stuff where the two people ahead of me ripped sidewalls on a rock. The rock ended up going up my sidewall (causing no damage) and bending the lip of the wheel. Just beat it back in to place and continued going.
Originally Posted By: hattaresguy
I run E rated tires because they are thicker and on job sites that's nice when it comes to nails and screws.
Did you have issues with the same tire in P-Metric regarding nails and screws or are you just being careful and figure the extra protection couldn't hurt?
Quote:
My truck scales at 4,400ish pounds normally loaded, my highest ever transfer station ticket was 6200.
See my Expedition scales over 6K with just me in it and something like 1/4 tank (curb weight is supposed to be something like 5,500). The tire size I used in my example above is the tire size the Expedition takes.
Quote:
The tires are rated for 3k each, at 80psi, so 12k pounds. I run between 40-45 so the ride is acceptable for a truck, so half that and I'm still way over my carrying capacity.
But what is the vehicle spec'd for? What's your stock tire size?
Quote:
I have run my E rated tires for almost 40k miles with good wear and no abnormal temperatures. Typically tires get hot and fail if they are under inflated at high speeds, under 40 doing short trips they don't really generate any heat. So even if say I'm loaded up to 6,200 I'm not running down I95 doing 70, I'm doing 25 for a mile to the transfer station. If that were my trucks typical usage I would up the pressure.
I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
I don't think so really. I set my tires by the placard and can run the Expie empty or loaded to the gills with a trailer behind it and I know my tire pressure is appropriate for all of it. I think the guys over-thinking it are those trying to justify the use of an LT in a P-metric application and don't really have a legitimate reason for it. I mean your reason at least makes sense (the job site thing), but for a truck (and particularly an SUV) that sees dirt roads, maybe the trail into the cottage and the rest of it highway, unless you want to have "Man Tires" and run some aggressive tread pattern to show how awesome you are, I don't really see the point in reducing load carrying capacity and ride quality because for some reason an LT tire, because it has "truck" in the name, is more appropriate than potentially the exact same tire (like the LTX A/S or M/S) in P-Metric in the size on the placard.
I'm not going to continue arguing over P-Metric or LT tires - I'm not changing your opinion and you aren't going to change mine.
As for the sidewall thickness, I have seen that first hand off road (I'm sure sometimes that's similar to a job site).
A lot of people end up running pmetric 2 ply all terrains off road. Sure, the tread is aggressive, but the first twig or rock they come to, then end up trashing a sidewall.
I've been through stuff where the two people ahead of me ripped sidewalls on a rock. The rock ended up going up my sidewall (causing no damage) and bending the lip of the wheel. Just beat it back in to place and continued going.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Miller88
I'm not going to continue arguing over P-Metric or LT tires - I'm not changing your opinion and you aren't going to change mine.
As for the sidewall thickness, I have seen that first hand off road (I'm sure sometimes that's similar to a job site).
A lot of people end up running pmetric 2 ply all terrains off road. Sure, the tread is aggressive, but the first twig or rock they come to, then end up trashing a sidewall.
I've been through stuff where the two people ahead of me ripped sidewalls on a rock. The rock ended up going up my sidewall (causing no damage) and bending the lip of the wheel. Just beat it back in to place and continued going.
Perhaps you missed my earlier statement:
Originally Posted By: OVERKILL
the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
I already acknowledged that if you off-road, LT tires can indeed make more sense. That is an aside from the load rating inflation topic.
I don't regularly go off-road with the Expedition and I doubt the OP is going to with his. They are big and the independent suspension version that he has doesn't have great ground clearance.
In order for something to make sense (like running LT's on a vehicle that doesn't call for them) you need to be able to lay out WHY. If somebody (like you) off-roads, then there is a potential benefit and perhaps having to be wary of inflation pressure relative to loaded weight is a worthwhile tradeoff in that scenario. Same with the example hattaresguy gave with jobs sites also somewhat justifying the use of a tire that may be more resistant to punctures and sidewall damage.
If neither of those scenarios in any way resemble how the OP uses his vehicle, what would be the reason for running a non-spec tire in his application? I can't think of one. He'd be better served just running the spec tire at the placard pressure and not have to worry about loading up his vehicle (which is already 6,000lbs) beyond the capabilities of the tires at the pressure they are inflated to.
I'm not going to continue arguing over P-Metric or LT tires - I'm not changing your opinion and you aren't going to change mine.
As for the sidewall thickness, I have seen that first hand off road (I'm sure sometimes that's similar to a job site).
A lot of people end up running pmetric 2 ply all terrains off road. Sure, the tread is aggressive, but the first twig or rock they come to, then end up trashing a sidewall.
I've been through stuff where the two people ahead of me ripped sidewalls on a rock. The rock ended up going up my sidewall (causing no damage) and bending the lip of the wheel. Just beat it back in to place and continued going.
Perhaps you missed my earlier statement:
Originally Posted By: OVERKILL
the only sensible reason to run them on it would be to do with the available selection of Off-road tires if the vehicle is wheeled where one would benefit from the thicker sidewall and beefier available tread patterns. If this in no way reflects the usage profile of the OP's Expedition, what is the benefit of going that route?
I already acknowledged that if you off-road, LT tires can indeed make more sense. That is an aside from the load rating inflation topic.
I don't regularly go off-road with the Expedition and I doubt the OP is going to with his. They are big and the independent suspension version that he has doesn't have great ground clearance.
In order for something to make sense (like running LT's on a vehicle that doesn't call for them) you need to be able to lay out WHY. If somebody (like you) off-roads, then there is a potential benefit and perhaps having to be wary of inflation pressure relative to loaded weight is a worthwhile tradeoff in that scenario. Same with the example hattaresguy gave with jobs sites also somewhat justifying the use of a tire that may be more resistant to punctures and sidewall damage.
If neither of those scenarios in any way resemble how the OP uses his vehicle, what would be the reason for running a non-spec tire in his application? I can't think of one. He'd be better served just running the spec tire at the placard pressure and not have to worry about loading up his vehicle (which is already 6,000lbs) beyond the capabilities of the tires at the pressure they are inflated to.
Originally Posted By: hattaresguy
......I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
Be careful. That type of thermometer doesn't measure that right thing. It's the internal to the tire temp that is important, and next in line would be the air chamber temperature. Measuring the surface temperature of a tire is closer to measuring the ambient air temperature.
......I have an IR thermometer and have never noticed a tire temperature difference between E and the original P's.
You guys are over thinking this.
Be careful. That type of thermometer doesn't measure that right thing. It's the internal to the tire temp that is important, and next in line would be the air chamber temperature. Measuring the surface temperature of a tire is closer to measuring the ambient air temperature.
quick update : I put 50PSI all around and drove 600miles yesterday to my destination ( joplin MO ), it drive fine, some time my check tires light on, but it go away. the tires does get hot when I touch it. it way above 50psi when got, around mabe 55psi. but over all im happy with 50psi, 47 would be perfect, but 50 is what I am running right now.
another 600 miles trip home on sunday.
another 600 miles trip home on sunday.
Originally Posted By: MetalSlug
quick update : I put 50PSI all around and drove 600miles yesterday to my destination ( joplin MO ), it drive fine, some time my check tires light on, but it go away. the tires does get hot when I touch it. it way above 50psi when got, around mabe 55psi. but over all im happy with 50psi, 47 would be perfect, but 50 is what I am running right now.
another 600 miles trip home on sunday.
Sounds good, 45-50 psi is what my Dad uses on his '03 F150 when not towing with the LT tires. No tire problems, or unusual wear doing that for many years now..
quick update : I put 50PSI all around and drove 600miles yesterday to my destination ( joplin MO ), it drive fine, some time my check tires light on, but it go away. the tires does get hot when I touch it. it way above 50psi when got, around mabe 55psi. but over all im happy with 50psi, 47 would be perfect, but 50 is what I am running right now.
another 600 miles trip home on sunday.
Sounds good, 45-50 psi is what my Dad uses on his '03 F150 when not towing with the LT tires. No tire problems, or unusual wear doing that for many years now..
OVERKILL
$100 Site Donor 2021
Originally Posted By: mrsilv04
And when we go all the way back to the first post, we see this:
"but when I bought this truck I check the pressure and its 46psi."
Well... it seems as if the original owner might have already had a good idea of what worked well.
Sounds like it
And when we go all the way back to the first post, we see this:
"but when I bought this truck I check the pressure and its 46psi."
Well... it seems as if the original owner might have already had a good idea of what worked well.
Sounds like it
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