P metric -vs LT tires - ride quality, MPG, etc.?

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I have a 2019 Tacoma, 4WD. I don't need tires yet, so I'm trying to research my options. I'm trying to decide if I should stick with P metric or consider an LT tire? My stock tire size is either 245/75R16 or optional 265/70R16. The tire that I'm most interested in is the Continental Terrain Contact A/T (https://continentaltire.com/tires/terraincontact-at) which is available in both P metric and LT for my truck.

Have any of you gone from P to LT, or vise-versa, in the same tire size (and maybe even the same brand?), if so, did you notice any change in ride quality, MPG, etc.

If I understand correctly, the biggest reason I might consider an LT tire is if I'm going to be either carrying heavy load(s) (which I currently do not, and likely won't ever) or towing a heavy load. I may decide to buy a small trailer, but for my peace of mind, relative to safety, I don't want one that's more than 1/2 of my max towing capacity, so that means approximately 3,000 lbs, or there about. I also don't currently do any off-road driving and any future off-roading will likely be "light"...I don't plan on driving the Rubicon.

:)

Should I just stick with the P metric tires or is there any specific reasons I might want to consider LT tires?

Thank you,
Ed
 
Switching to LT tires, even in the same size will probably get you a 2mpg decrease in mileage. I've been down this road before with both a Tacoma and a 4Runner. I lifted both vehicles and had 33" E load range LT tires. Its simply the increased weight/rotational mass of the tire that causes it. LT tires definitely ride more firm, but you can play around with tire pressures to some degree. If you are carrying/towing heavier loads, you need to air up the LT tires to their max pressure to prevent heat buildup. C rated are usually around 55psi, E rated 80psi, and they will ride like round rocks at that point. I kept mine at 35psi all around on both. In winter, I dropped them to 28-30psi for a little better traction. A good compromise is a 'C' load range rated LT tire, but you will still take a hit to your mpg. LT tires can also be a pain to get and keep balanced, don't be surprised to see 5oz of wheel weights on them. I have always opted for a road force balance, especially with Toyota trucks, and never had any issues. They are well known to have vibration issues around 50-70 mph if the balancing isn't done correctly.
 
An LT tire will ride rougher and stiffer as it requires a higher air pressure to carry the same load. The LT tire will also weigh more, which doesn't help the ride and hurts fuel economy.

An advantage is that the LT tire often has deeper tread depth to start with, and the LT tire is typically more resistant to chunking and other types of tire damage.

You are aren't proposing to load up heavy or tow heavy, nor have you described any defect in the current ride and handling. Why would you go to an LT in that case?

(And yes, I've gone back an forth - the LT tire made sense in some uses, but not what you are describing).
 
I wouldn't do it just for the fact your truck wasn't designed to run them. I have LT's on my old Sierra but that's what it calls for and I run them at 45 psi to make it more tolerable, 50 psi and you need a mouth guard.
 
I'm going to explain why what 208vette and MN gopher say is correct.

LT tires are made from a harder rubber because they are designed to carry more load and the rubber used in P type tires will permanently deform under those levels of loading.. Mushrooming is a term that is sometimes applied to this deformation.

As a result, not only do LT tires need to use more inflation pressure to carry the same load - and so they ride worse - they also get worse fuel economy. The plus side is that they get more cut resistance, and better wear.
 
I've switched over to LT tires from P tires on numerous trucks and SUV's. The reason is always for better tire durability on 4wd trails. Every time I took a P rated tire on a 4wd trail, I've gotten a puncture. With the LT tires it's been decades since I had a puncture, off-road.

The ride is a bit firmer, but not bad IMO. MPG will be impacted, but in my latest use case with the same 'size' (P 265/70R17
vs LT 265/70R17 E) the MPG difference is less than 1 MPG.

P rated tires also have a a reduced load capacity by a factor of 1.1, when mounted on Trucks or SUV's per FMVSS.
 
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Something else to consider... with the higher pressures of the LT tires, it may set off your TPMS every time you start the truck.
Never heard of a TPMS system that alerts the driver of too high air pressure, just when the pressure drop below the acceptable threshold (direct sensor) or if the rotation rate deviates significantly between tires (indirect monitoring).
 
I've switched over to LT tires from P tires on numerous trucks and SUV's. The reason is always for better tire durability on 4wd trails. Every time I took a P rated tire on a 4wd trail, I've gotten a puncture. With the LT tires it's been decades since I had a puncture, off-road.

The ride is a bit firmer, but not bad IMO. MPG will be impacted, but in my latest use case with the same 'size' (P 265/70R17
vs LT 265/70R17 E) the MPG difference is less than 1 MPG.

P rated tires also have a a reduced load capacity by a factor of 1.1, when mounted on Trucks or SUV's per FMVSS.

Yes-but most "P" rated tires can carry the load range of the truck. Your reason for buying LT tires, for-off-road use is one of the few valid reasons for going with LT on a light duty truck.
 
I've switched over to LT tires from P tires on numerous trucks and SUV's. The reason is always for better tire durability on 4wd trails. Every time I took a P rated tire on a 4wd trail, I've gotten a puncture. With the LT tires it's been decades since I had a puncture, off-road.

The ride is a bit firmer, but not bad IMO. MPG will be impacted, but in my latest use case with the same 'size' (P 265/70R17
vs LT 265/70R17 E) the MPG difference is less than 1 MPG.

P rated tires also have a a reduced load capacity by a factor of 1.1, when mounted on Trucks or SUV's per FMVSS.
Offroad is definitely a valid reason. I remember when the Duratracs came out, everyone was running them. MOST people bought P metric instead of LT. Pretty much everyone running the P metric duratracs lost a sidewall at least once. The LT ones held up a LOT better.
 
I'm going to explain why what 208vette and MN gopher say is correct.

LT tires are made from a harder rubber because they are designed to carry more load and the rubber used in P type tires will permanently deform under those levels of loading.. Mushrooming is a term that is sometimes applied to this deformation.

As a result, not only do LT tires need to use more inflation pressure to carry the same load - and so they ride worse - they also get worse fuel economy. The plus side is that they get more cut resistance, and better wear.
And how does that harder rubber compare regarding on the road traction ?
 
I've switched over to LT tires from P tires on numerous trucks and SUV's. The reason is always for better tire durability on 4wd trails. Every time I took a P rated tire on a 4wd trail, I've gotten a puncture. With the LT tires it's been decades since I had a puncture, off-road.

The ride is a bit firmer, but not bad IMO. MPG will be impacted, but in my latest use case with the same 'size' (P 265/70R17
vs LT 265/70R17 E) the MPG difference is less than 1 MPG.

P rated tires also have a a reduced load capacity by a factor of 1.1, when mounted on Trucks or SUV's per FMVSS.

This is what I've found on the numerous forums I've visited to answer the same question about changing to LT tires:

pros: Firmer ride, more durable, longer lasting, heavier loads and better cut resistance on the trail.

cons: Heavier, more expensive, and less traction in the rain (and possibly in snow as well)

MPG is a mixed bag and depends heavily on the type of driving done. If there's lots of in-town stop and go, then the LT will cost a couple mpg or more. Highway drivers say that their mpg is pretty much the same - seems that once rolling, the momentum of the tire keeps it moving.

If you do a lot of offroad driving, then the LT is for you. If mostly street, especially stop and go, then the P rated.

Towing is another animal and would depend on the weight of the trailer. If you're towing something light, P will be fine. But going to the max possible for the vehicle - and towing a lot - you may want to invest in LT. Keep in mind that most P metrics can be inflated well beyond what's on the door jamb, which will add some stiffness under heavy load. In fact, I did this with my 4Runner when towing 5,000# a couple years ago. It was squirmy in the rear end, but once I fully inflated the tires it was rock steady.

Hope this helps.
 
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Offroad is definitely a valid reason. I remember when the Duratracs came out, everyone was running them. MOST people bought P metric instead of LT. Pretty much everyone running the P metric duratracs lost a sidewall at least once. The LT ones held up a LOT better.
Yep. Real cowboys don't line-dance.
 
Never heard of a TPMS system that alerts the driver of too high air pressure, just when the pressure drop below the acceptable threshold (direct sensor) or if the rotation rate deviates significantly between tires (indirect monitoring).

Happens to me with my titan when I crank up the pressure in the rears doing heavy towing.
 
I'm a little surprised by the MPG loss reports-harder rubber, less sidewall flexing, less rubber on the road (with any load at all) should mean less heat & less fuel consumption. Unless we're comparing mud tires to all-season P metric, I'm not getting it.
 
And how does that harder rubber compare regarding on the road traction ?
The same technology triangle involving treadwear, traction, and rolling resistance that applies to Passenger car tires, also applies to LT tires - EXCEPT: No one is asking heavy duty pickup tires to have sports car like grip or econocar levels of rolling resistance.

In other words, it can be compensated for.

I'm a little surprised by the MPG loss reports-harder rubber, less sidewall flexing, less rubber on the road (with any load at all) should mean less heat & less fuel consumption. Unless we're comparing mud tires to all-season P metric, I'm not getting it.
Except that a harder rubber doesn't really mean less sidewall flexing since it is the inflation pressure that controls most of the sidewall stiffness.

- AND -

Most of the RR occurs in the tread compound and there a harder rubber results in more internal friction to flex.
 
This is what I've found on the numerous forums I've visited to answer the same question about changing to LT tires:

pros: Firmer ride, more durable, longer lasting, heavier loads and better cut resistance on the trail.

cons: Heavier, more expensive, and less traction in the rain (and possibly in snow as well)

MPG is a mixed bag and depends heavily on the type of driving done. If there's lots of in-town stop and go, then the LT will cost a couple mpg or more. Highway drivers say that their mpg is pretty much the same - seems that once rolling, the momentum of the tire keeps it moving.

If you do a lot of offroad driving, then the LT is for you. If mostly street, especially stop and go, then the P rated.

Towing is another animal and would depend on the weight of the trailer. If you're towing something light, P will be fine. But going to the max possible for the vehicle - and towing a lot - you may want to invest in LT. Keep in mind that most P metrics can be inflated well beyond what's on the door jamb, which will add some stiffness under heavy load. In fact, I did this with my 4Runner when towing 5,000# a couple years ago. It was squirmy in the rear end, but once I fully inflated the tires it was rock steady.

Hope this helps.

I put "XL" rated tires on my truck. With the exception of the F-150s "Max Tow" package" which gives the truck more capability than most half-tons, the "XL" rated tires will handle what one SHOULD TOW with a half-ton.
 
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