LT vs P rated tires on trucks and treadwear?

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A lot of people put heavier LT, E rated tires on their trucks as replacement for the stock P rated tires. I know the extra unsprung weight is a disadvantage, but many claim they wear more evenly and that the extra plies, along with more tread depth, are worth the extra price and slight hit in mpg.

Has anyone heard of E rated tires wearing more evenly than a P rated tire would? When 30+ psi is causing me excessive center treadwear on my back tires, there are others with my truck type running E rated tires at 55psi claiming they wear evenly.

Could the extra plies just make them so much more rigid in their molded shape that, regardless of the extra psi, they maintain even tread contact?
 
Only thing you'll sacrifice is ride quality/smoothness-there will be more bouncing over bumps due to the stiffer sidewalls & higher pressure, but they'll work.
 
Pickups should NOT come with low weight rated P tires! It's a pickup, it's supposed to ride rough.

I have E rated tires on my jeep in the summer and D in the winter. Doesn't ride like a cadillac
 
After my original set of 4 -P245/70R16 Michelins wore out, my brother gave me a free half worn out set of 4 that were LT265/75R16 Michelins he didn't need. My old set made my Silverado ride better than our Impala LS. The E rated tires on my truck now make even small bumps alot more noticeable. I keep them at inflated at 50psi instead of the 75 they recommend just to help with the ride. Either tires wore very nicely and got nearly 90,000 miles on my first set (granted not much left of them). After my income tax refund, P255/70R16 Michelins are going back on. Can't wait.
 
This is confusing. Are you saying that your truck's original tires were Michelins in size P245/70R16 and that GM recommends inflating them to 75psi cold?
 
My 01 Silverado 1/2 ton 4x4 had 265/75/16's on it originally. I replaced with Mich. LT 265/75/16. New tires have over 40k on them and are wearing great. I have been running them at 36 psi,factory recommended pressure listed on the door placard.

Does the LT tire recommended pressure increase apply to tires that did not have the P (passenger)designation originally?
 
I have run both LT E rated tires and P metric on several vehicles. I would not suggest LT with E rating for smaller vehicles (Tacoma, Jeep Cherokee, etc.) as the ride is too stiff. However, on larger trucks (F150, Silverado, etc.) that haul loads they work and ride quite well.

LT tires with load range C or D seem to ride fine on smaller vehicles and compare well to P metric sizes.

LT tires typically have a lower treadwear warranty than P metric sizes within the same tire model in my experience.
 
Originally Posted By: yonyon
This is confusing. Are you saying that your truck's original tires were Michelins in size P245/70R16 and that GM recommends inflating them to 75psi cold?


No, he said...

Quote:
The E rated tires on my truck now make even small bumps alot more noticeable. I keep them at inflated at 50psi instead of the 75 they recommend just to help with the ride.
 
10 ply LT tires will by far outlast any p-metric equivalent if you are driving a heavy or consistently loaded vehicle. LT tires resist misshaping under load, and can maintain an even tread footprint when under load.

Contrary to belief, the rubber compound between an LT and p-metric tire (same tire model, same manufacturer) is the same, the difference is the tires inner construction. If you drive a 1/2 ton pickup that is empty 99% of the year, than you can expect a p-metric tire to have the same tread life as an LT tire.

Weight capacity aside, most 10 ply tires have better puncture/cut resistance and that's why I buy them for my pickups.
 
The tread wear depends on the applaction. A 1/2 ton on E range tires will most certianly get much better (more milage) but will beat you 2 death when unloaded.

On 3/4 on heaver u need/want E range. Its a heaver tire for a heaver truck.

i've owned both and the 1/2 ton came with the Lt 265/75/16 load range C. So 1/2 can come with either LT or P.

3/4 I own, a p metric wouldn't hold up the truck (not enough capacity). Due to the heaver weight i get about half the tread wear then someone in a 1/2ton.

So it's easy to see why when you put a higher load range tire on a light truck why it (1/2 ton) would have better tread milage the a heaver truck.
 
We had a company van (E-350) that PepBoys somehow put P-rated 245/70R16s on-in addition to being be dangerous to drive, wore them out in under 30,000 miles. If you're going to haul weight, use the LTs, you can always drop the pressure to 45 PSI if the ride is too rough.
 
E rated tires ruin the trucks ride, but I run them on my half ton because they are less prone to get screws and nails stuck into them.

On job sites the thicker tires are nice.

I run 40psi in them, if I cranked it up to where they are supposed to be 70 I think the ride would truly be awful.
 
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A lot of people put heavier LT, E rated tires on their trucks as replacement for the stock P rated tires. ... and that the extra plies,
What extra plies? A Load Range E tire probably has three plies of tire code in the sidewalls (except the Michelin XPS with one ply), and a Standard Load pick up truck tire probably has two plies. A Load Range D tire might have two or three.

Recommended pressure of 70 or 75 psi???...only in a 250/2500 or 350/3500 pickup at full load. The tire's sidewall fine print says that the Load Range E tire must have a minimum of 80 psi when carrying the max load listed on the sidewall.

The real recommended tire pressure?...right here:
http://www.michelintruck.com/michelintruck/tires-retreads/load-inflation-tables.jsp

For some reason that we need a tire pro to explain, an LT tire needs more pressure to carry the same load as a P tire of the same size.
 
I just put a set of takeoff Firestone Transforce AT LT265/70R17E on my F150 Lariat 4x2 SuperCrew. They put 35 psi in them at the Firestone place. They do ride rougher than my old Michelin X Radial LT P265/70R17 that I just took off which I kept at 32psi. I would have probably put Ps back on there if I hadn't found such a good deal on these takeoffs. The Firestone place sold me a lifetime rotation, lifetime balance, free flats and road hazard on them just like as if they were new tires.
 
Originally Posted By: Ken2
For some reason that we need a tire pro to explain, an LT tire needs more pressure to carry the same load as a P tire of the same size.


It's a "buffer", so to speak, given the loading and usage conditions that are expected in light trucks.

Reduce the load capacity of a P-metric by a factor of 1.10 (as FMVSS dictates when installed on light trucks), and the differentiation you mention will disappear.
 
CapriRacer has explained this P->LT thing so many times that he could probably puke...

And here's yet another thread on it.
 
One year I tried to inflate the LRE tires on one of the Jeeps to 80PSI. The jeep was, quite literally, leaving the pavement on expansion joints!


I do like the LRE tires off road. Much thicker sidewalls and are not prone to blowing out on roots.
 
Originally Posted By: Boomer
Remember, LT tires require higher pressure to carry the same weight a P tire can carry at lower pressure.

http://www.nittotire.com/Content/pdf/Rep...%20Bulletin.pdf

So yes, I would assume they would wear more evenly at higher pressures.


That was an interesting read. My truck came from the dealer with low 40psi in the tires to keep the tmps light off (with a max inflation pressure of 35 psi listed on the tire sidewall), so I already know how that rides on the interstate. I really wouldn't want to have to run an LT tire above 45psi.

It would be worth the rougher ride to me if I didn't get the excessive center tread wear I get now with an empty bed. With a curb weight of 4,315lbs, the rear tires wouldn't have much weight on them 99.9% of the time.
I also like the idea of more puncture resistant sidewalls while offroading.
 
Originally Posted By: CurtisB
.... Contrary to belief, the rubber compound between an LT and p-metric tire (same tire model, same manufacturer) is the same, the difference is the tires inner construction.......


Sorry, but both the construction AND the rubber compounds are different between LT and P type tires - even in the same tire model. The reason for that is that LT tires have what I call "more unit loading" - that is loading compared to the physical dimensions - and that causes some rubber compounds to "compression set" - which is a form of "material creep" - where the rubber permanently deforms due to the heavy loading. As a result, LT tires use different rubber compounds - ones that have higher hysteresis and that results in lower fuel economy.

No, this is NOT what tires flat spot. That's a different phenomenon.
 
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