What tire pressure for these new truck tires?

Chris B. said:
These are the 26575R16 original factory size. They are LT tires. ........
Click to expand...

I usually don't contract an OP, but in this case, I'm gonna.

The original tires on the truck were P type tires. One of the clues was 35 psi!

OP: Look at the vehicle tire placard on the driver's door frame to verify.

If that is the case, then the new LT type tires will need 50 psi to carry the same load as the original P type tires.
 
I run LT type tires on my 3/4 ton Chevy. I sometimes have the local Cal Tire air them up for me. The tech always goes straight to the door sticker for the numbers. 50 psi front, 60 psi back.

Check your sticker. Is it for P type tires or LT. If your new tires are LT, you can certainly go up a bit.
 
CapriRacer said:
I usually don't contract an OP, but in this case, I'm gonna.

The original tires on the truck were P type tires. One of the clues was 35 psi!

OP: Look at the vehicle tire placard on the driver's door frame to verify.

If that is the case, then the new LT type tires will need 50 psi to carry the same load as the original P type tires.
Click to expand...
I had the same deal on my 1991 Ford F-150. The truck was delivered new with P 235 X 15 passenger car tires. I would have to look, but I believe the door sticker had either 32 or 35 PSI as max.

The truck looked stupid with them, and drove and handled worse. They were all but bald after 20,000 miles. I then replaced them with LT rated 31 X 10.5 X 15's. I've been running that size at 42-45 PSI for the last 140,000 miles. And have never looked back.
 
Google apears to be not the most reliable source.
First found LI 112/109 AT 50 psi.
But now I found Loadindexes 114, 119, 123 for singleload.
One 119 gave XL wich AT 42psi.
And 123 gave 10pr wich is E-load AT 80 psi mostly.
That close together that I think Exeption to the rule mayby E-load AT 65psi.
Or the personscar have a history of to high given maxload/loadindex.

So my question again to topicstarter.
Look on sidewall for the exact specifications, so I can make a correct list.
Then also give your GAWR's and GVWR.
Mayby on this 26 year old car ( when I read it right) not yet the now official tire and pressure plate is given with yellow in it.

In Europe, where I live, since 1980 it is prescribed to give a VIN plate ( Vehicle Indentification Number) on the car somewhere, with GAWR's and GVWR, and Gross combined Vehicle weight.
 
Last edited:
jadatis said:
Google apears to be not the most reliable source.
First found LI 112/109 AT 50 psi.
But now I found Loadindexes 114, 119, 123 for singleload.
One 119 gave XL wich AT 42psi.
And 123 gave 10pr wich is E-load AT 80 psi mostly.
That close together that I think Exeption to the rule mayby E-load AT 65psi.
Or the personscar have a history of to high given maxload/loadindex.

So my question again to topicstarter.
Look on sidewall for the exact specifications, so I can make a correct list.
Then also give your GAWR's and GVWR.
Mayby on this 26 year old car ( when I read it right) not yet the now official tire and pressure plate is given with yellow in it.

In Europe, where I live, since 1980 it is prescribed to give a VIN plate ( Vehicle Indentification Number) on the car somewhere, with GAWR's and GVWR, and Gross combined Vehicle weight.
Click to expand...
Sorry for the delay! Here is a picture of the info on my door jam. Hopefully this is the info you need. Also a better picture of the side if the tire. It is a LT265/75R16 123/1200. also says max load single 1550kg 3415lbs at 550 kpa (80psi) cold. Max load dual 1400kg 3080lbs at 350kpa (80lbs). Load range E. Plies: tread 2, Polyester +2, Steel + 2 Nylon, Sidewall 2 Polyester GL-486-D M=S snowflake inside mountain shape.
3WupIkb.jpg

Zc5MdN9.jpg
 
CapriRacer said:
I usually don't contract an OP, but in this case, I'm gonna.

The original tires on the truck were P type tires. One of the clues was 35 psi!

OP: Look at the vehicle tire placard on the driver's door frame to verify.

If that is the case, then the new LT type tires will need 50 psi to carry the same load as the original P type tires.
Click to expand...
3WupIkb.jpg

Zc5MdN9.jpg
 
That chanches a lot.
Made new list, forget the list I gave earlyer.
And because also GAWR's given, we dont need to know what the maxload of the P tires where.
Your GAWR's together 7675lbs, and GVWR 6200LBS, gives a comfortable reserve of 1475lbs to shift some weight.
Could indicate that GVWR can be upgraded. Also rear lower then front is peculiar but seen more often at verry smaller european cars.

But because of 6200lbs GVWR, and you dont overload, you could considder to use the psi for 3100lbs is 38 psi. Only driver and lightloaded even less. Then 35 psi would still not overheat the tires when driving 99mph.
That you never drive 99mph gives extra reserve.
But estimating the axleload is dangerous. Only weighing per axle, or better per wheel, makes it 99% certain.

Because my list did not go lower then 36 psi in the spreadsheet, I chanched after copying and pasting in this post, to steps of 2psi, and copied and pasted from 34psi and lower
My advice is to look in the lbs list behind the psi with 90% given of loadcapacity calculated for the pressure.

Axle100% / cold psi/ axle 90% used
1942 lbs/ 20 psi / 1748 lbs
2112 lbs/ 22 psi / 1900 lbs/ lowest in EUR
2280 lbs/ 24 psi / 2052 lbs
2448 lbs/ 26 psi / 2204 lbs/lowest in US
2616 lbs/ 28 psi / 2354 lbs
2783 lbs/ 30 psi / 2504 lbs
2949 lbs/ 32 psi / 2654 lbs
3115 lbs/ 34 psi / 2803 lbs

3280 lbs/ 36 psi / 2952 lbs
3362 lbs/ 37 psi / 3026 lbs
3445 lbs/ 38 psi / 3100 lbs
3527 lbs/ 39 psi / 3174 lbs
3609 lbs/ 40 psi / 3248 lbs
3691 lbs/ 41 psi / 3322 lbs
3773 lbs/ 42 psi / 3396 lbs
3855 lbs/ 43 psi / 3469 lbs
3937 lbs/ 44 psi / 3543 lbs
4018 lbs/ 45 psi / 3616 lbs
4100 lbs/ 46 psi / 3690 lbs
4181 lbs/ 47 psi / 3763 lbs/ 3750 GAWR R
4263 lbs/ 48 psi / 3836 lbs
4344 lbs/ 49 psi / 3909 lbs
4425 lbs/ 50 psi / 3983 lbs/ 3925 GAWR Fr
4506 lbs/ 51 psi / 4056 lbs
4587 lbs/ 52 psi / 4128 lbs
4668 lbs/ 53 psi / 4201 lbs
4749 lbs/ 54 psi / 4274 lbs
4830 lbs/ 55 psi / 4347 lbs
4911 lbs/ 56 psi / 4420 lbs
4991 lbs/ 57 psi / 4492 lbs
5072 lbs/ 58 psi / 4565 lbs
5153 lbs/ 59 psi / 4637 lbs
5233 lbs/ 60 psi / 4710 lbs
5313 lbs/ 61 psi / 4782 lbs
5394 lbs/ 62 psi / 4854 lbs
5474 lbs/ 63 psi / 4927 lbs
5554 lbs/ 64 psi / 4999 lbs
5634 lbs/ 65 psi / 5071 lbs
5714 lbs/ 66 psi / 5143 lbs
5794 lbs/ 67 psi / 5215 lbs
5874 lbs/ 68 psi / 5287 lbs
5954 lbs/ 69 psi / 5359 lbs
6034 lbs/ 70 psi / 5431 lbs
6114 lbs/ 71 psi / 5502 lbs
6194 lbs/ 72 psi / 5574 lbs
6273 lbs/ 73 psi / 5646 lbs
6353 lbs/ 74 psi / 5718 lbs
6432 lbs/ 75 psi / 5789 lbs
6512 lbs/ 76 psi / 5861 lbs
6591 lbs/ 77 psi / 5932 lbs
6671 lbs/ 78 psi / 6004 lbs
6750 lbs/ 79 psi / 6075 lbs
6830 lbs/ 80 psi / 6147 lbs/ referencepress
6909 lbs/ 81 psi / 6218 lbs
6988 lbs/ 82 psi / 6289 lbs
7067 lbs/ 83 psi / 6360 lbs
7146 lbs/ 84 psi / 6432 lbs
7225 lbs/ 85 psi / 6503 lbs
7304 lbs/ 86 psi / 6574 lbs
7383 lbs/ 87 psi / 6645 lbs
7462 lbs/ 88 psi / 6716 lbs
7541 lbs/ 89 psi / 6787 lbs
7620 lbs/ 90 psi / 6858 lbs
 
Last edited:
Yes it does. lower max pressure( referencepressure) belonging to lower loadrange gives higher loadcapacity for the same pressure.
This leads to lower needed pressure for the same load on tire.
For that reason for instance E-load of same size needs about 15psi higher for the same load on tire, then a P-tire standard load. Same goes when going from C-load to E-load.

But CapriRacer knows that, wrote it in post #21. Think he had a little temporarely black out when he wrote the post above this.
 
Last edited:
jadatis said:
That chanches a lot.
Made new list, forget the list I gave earlyer.
And because also GAWR's given, we dont need to know what the maxload of the P tires where.
Your GAWR's together 7675lbs, and GVWR 6200LBS, gives a comfortable reserve of 1475lbs to shift some weight.
Could indicate that GVWR can be upgraded. Also rear lower then front is peculiar but seen more often at verry smaller european cars.

But because of 6200lbs GVWR, and you dont overload, you could considder to use the psi for 3100lbs is 38 psi. Only driver and lightloaded even less. Then 35 psi would still not overheat the tires when driving 99mph.
That you never drive 99mph gives extra reserve.
But estimating the axleload is dangerous. Only weighing per axle, or better per wheel, makes it 99% certain.

Because my list did not go lower then 36 psi in the spreadsheet, I chanched after copying and pasting in this post, to steps of 2psi, and copied and pasted from 34psi and lower
My advice is to look in the lbs list behind the psi with 90% given of loadcapacity calculated for the pressure.

Axle100% / cold psi/ axle 90% used
1942 lbs/ 20 psi / 1748 lbs
2112 lbs/ 22 psi / 1900 lbs/ lowest in EUR
2280 lbs/ 24 psi / 2052 lbs
2448 lbs/ 26 psi / 2204 lbs/lowest in US
2616 lbs/ 28 psi / 2354 lbs
2783 lbs/ 30 psi / 2504 lbs
2949 lbs/ 32 psi / 2654 lbs
3115 lbs/ 34 psi / 2803 lbs

3280 lbs/ 36 psi / 2952 lbs
3362 lbs/ 37 psi / 3026 lbs
3445 lbs/ 38 psi / 3100 lbs
3527 lbs/ 39 psi / 3174 lbs
3609 lbs/ 40 psi / 3248 lbs
3691 lbs/ 41 psi / 3322 lbs
3773 lbs/ 42 psi / 3396 lbs
3855 lbs/ 43 psi / 3469 lbs
3937 lbs/ 44 psi / 3543 lbs
4018 lbs/ 45 psi / 3616 lbs
4100 lbs/ 46 psi / 3690 lbs
4181 lbs/ 47 psi / 3763 lbs/ 3750 GAWR R
4263 lbs/ 48 psi / 3836 lbs
4344 lbs/ 49 psi / 3909 lbs
4425 lbs/ 50 psi / 3983 lbs/ 3925 GAWR Fr
4506 lbs/ 51 psi / 4056 lbs
4587 lbs/ 52 psi / 4128 lbs
4668 lbs/ 53 psi / 4201 lbs
4749 lbs/ 54 psi / 4274 lbs
4830 lbs/ 55 psi / 4347 lbs
4911 lbs/ 56 psi / 4420 lbs
4991 lbs/ 57 psi / 4492 lbs
5072 lbs/ 58 psi / 4565 lbs
5153 lbs/ 59 psi / 4637 lbs
5233 lbs/ 60 psi / 4710 lbs
5313 lbs/ 61 psi / 4782 lbs
5394 lbs/ 62 psi / 4854 lbs
5474 lbs/ 63 psi / 4927 lbs
5554 lbs/ 64 psi / 4999 lbs
5634 lbs/ 65 psi / 5071 lbs
5714 lbs/ 66 psi / 5143 lbs
5794 lbs/ 67 psi / 5215 lbs
5874 lbs/ 68 psi / 5287 lbs
5954 lbs/ 69 psi / 5359 lbs
6034 lbs/ 70 psi / 5431 lbs
6114 lbs/ 71 psi / 5502 lbs
6194 lbs/ 72 psi / 5574 lbs
6273 lbs/ 73 psi / 5646 lbs
6353 lbs/ 74 psi / 5718 lbs
6432 lbs/ 75 psi / 5789 lbs
6512 lbs/ 76 psi / 5861 lbs
6591 lbs/ 77 psi / 5932 lbs
6671 lbs/ 78 psi / 6004 lbs
6750 lbs/ 79 psi / 6075 lbs
6830 lbs/ 80 psi / 6147 lbs/ referencepress
6909 lbs/ 81 psi / 6218 lbs
6988 lbs/ 82 psi / 6289 lbs
7067 lbs/ 83 psi / 6360 lbs
7146 lbs/ 84 psi / 6432 lbs
7225 lbs/ 85 psi / 6503 lbs
7304 lbs/ 86 psi / 6574 lbs
7383 lbs/ 87 psi / 6645 lbs
7462 lbs/ 88 psi / 6716 lbs
7541 lbs/ 89 psi / 6787 lbs
7620 lbs/ 90 psi / 6858 lbs
Click to expand...
Thanks for all of that! Honestly this is still over my head. Not sure what all the different numbers are for and what they mean. What PSI would you set these tires to? I normally have less then 500lbs in the bed at any given time. once a year I have about 2,000lbs in the bed when transporting fire stove pellets.
 
I am going to reply to all of the below in one post. Hope this works!

Chris B. said:
Right but the tired need more air/PSI in them vs. the P tires to carry the same weight is what I understand. So these LT tires need like 40-45psi?
Click to expand...
Chris B. said:
So 50psi for daily driving without a heavy load in the bed? What PSI if I have say 1500-2000lbs in the bed?
Click to expand...
jadatis said:
Yes it does. lower max pressure( reference pressure) belonging to lower load range gives higher load capacity for the same pressure.
This leads to lower needed pressure for the same load on tire.
For that reason for instance E-load of same size needs about 15psi higher for the same load on tire, then a P-tire standard load. Same goes when going from C-load to E-load.

But CapriRacer knows that, wrote it in post #21. Think he had a little temporarily black out when he wrote the post above this.
Click to expand...

First, what I meant - and what I thought I was replying to - was that the new LT tires the OP has have the same load carrying capacity at 50 psi, regardless if they have a 50 psi max or an 80 psi max. Put another way, Load Range C vs Load Range E!

And - NO! - the 50 psi is the pressure needed to carry the max load. I know that many people think that you can (should?) use a lower pressure when the truck bed is empty, but the vehicle manufacturer didn't say that - and, in fact, tested the truck both empty and fully loaded at the same pressure (35 psi) and set up the springs, shocks and sway bars, so that it worked at the same inflation pressure for both loaded and unloaded conditions. Complicating this is that LT tires need that increased pressure to carry the load - and since the OP isn't going to conduct a test to verify that the 50 psi works or doesn't work for both conditions, the conservative thing to do is to do as closely as possible what the vehicle manufacturer says - which is same pressure front to rear.

And many will say they shouldn't put so much pressure in the tires because they'll wear out in the center - that they want even wear - to which I point out that radial tires are less sensitive to the wear vs pressure thing than the bias tires - and that what dominates tire wear is the positional effect of drive tires wearing in the center and steer tires wearing in the shoulders, so frequent tire rotation is called for to balance this out - rather than inflation pressure adjustments.
 
In my list I gave the GAWR's at front 50 psi, and rear 47 psi. So assuming you still dont overload the axles with your 2000 lbs in the bed ( explain bed to this european guy). You can use those pressures and drive 99mph constantly.
You probably wont drive that if the pellets come from 2 blocks away.
And at lower speed the tires heat up less, so higher loadcapacity for the same pressure.

I studied the system the tiremakers use for that, and the larger ST tires are calculated in maxload for 65mph, and then mostly have 6 loadindex steps higher. Your size and E-load ( AT 80 psi) for instance if available in ST( special trailer), then would have loadindex 123+6= 129 loadindex.

But could also make a list for your tire with loadcapacity's for 65mph. Will not confuse you with that.

So it all comes down to determine the axleloads in your given situations.
And that is the tricky part.

Can make a (dangerous) estimation, if you can give the empty weight of the car.

My suspicion is that with 2000 in the back, the GVWR of 6200 lbs is overloaded, and most likely also the GAWR rear.

Once you determined the axleloads acurate its a piece of cake.
Yust search them back in my made list behind the psi, and read the psi in front of it.
 
Last edited:
jadatis said:
In my list I gave the GAWR's at front 50 psi, and rear 47 psi. So assuming you still dont overload the axles with your 2000 lbs in the bed ( explain bed to this european guy). You can use those pressures and drive 99mph constantly.
You probably wont drive that if the pellets come from 2 blocks away.
And at lower speed the tires heat up less, so higher loadcapacity for the same pressure.

I studied the system the tiremakers use for that, and the larger ST tires are calculated in maxload for 65mph, and then mostly have 6 loadindex steps higher. Your size and E-load ( AT 80 psi) for instance if available in ST( special trailer), then would have loadindex 123+6= 129 loadindex.

But could also make a list for your tire with loadcapacity's for 65mph. Will not confuse you with that.

So it all comes down to determine the axleloads in your given situations.
And that is the tricky part.

Can make a (dangerous) estimation, if you can give the empty weight of the car.

My suspicion is that with 2000 in the back, the GVWR of 6200 lbs is overloaded, and most likely also the GAWR rear.

Once you determined the axleloads acurate its a piece of cake.
Yust search them back in my made list behind the psi, and read the psi in front of it.
Click to expand...
Thanks again! So what is it about the P tires that needed 35PSI but the LT tires need 50psi? I thought the LT tires are more "heavy duty" then P tires? Thanks again!
 
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