LT vs P-metric

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Oldswagon

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I am looking at a set of new tires soon for my Suburban. I am leaning towards the Kuhmo Road Venture SAT KL61 tires, but I am also considering BF Goodrich All-Terrian tires.

The tire dealer I deal with is really pushing the "LT" tires over the P tires for the Kuhmo's, while the BFG's only come in LT. The LT tires will cost about $100 more. He seems to think that they will carry the weight of my heavy Suburban better than the P tires and will last longer.

Looking at the specs, both the BFG's and the Kuhmo's in LT actually have a lower load rating than the P tires. Both LT tires are 6-ply, vs 4-ply for the P tires.

So, what are the advantages to the LT tire?? Is the dealer feeding me a line to make more money?
 
I'd stick with what your truck came with. With the LT tires, you'll have to run a higher pressure to drive safely. The "ply rating" can be mostly marketing, it's hard to tell.

If your truck came with P-metric tires, I'd stick with those. If it came with LT tires from the factory, then I'd stick with those.
 
I agree, read the door jamb, and see what the truck came with.

Honestly, with a suburban, I might consider LT tires.

I had a 98 f150 Jack Roush edition, that had P tires on it, anything heavier would be LT.
 
Oldswagen, The sticker on the driver side door post tells you the tire that the factory recommends. Lacking other info as to how you load up the Suburban, I would go with that. FWIW-- Oldtommy
 
What are you hauling in it? People? Then the P-metric tires may give a better ride and be easier to find good wet traction. If you regularly pile the back full of stuff or tow, better look at the LT.
 
I would listen to the tire guy. I know the 3/4 ton Suburbans came with 10 ply tires (load range E). I can't imagine anything less than load range D on any Suburban, but you didn't give specifics about your rig.
 
I haul more cargo/supplies than people with the truck, but it is often driven empty as well. Ride isn't really a big concern. I want long tread life and good traction.

The LT tires only have a 104 load rating (load range C), the P-metric 105. Stock tires are P235/75-15 XL which actually have a 108 load rating (Kuhmo doesn't make the XL tire). The GVWR is about 7200 if I remember correctly. So even the 104 load rating should be okay for the truck.

What I don't understand is if the LT tires are supposed to be better for high loads, why do the have a lower load rating?

BFG All-Terrian (only available in LT)

LT235/75R15/C 104S

MAX Load 1985 @50PS1

Kumho SAT KL61

P235/75R15 105S

MAX LOAD 2028 @ 51 PSI

LT235/75R15 104/101S

MAX LOAD 1985 @ 50 PSI


The 'burb is 1993 C1500 2WD 1/2 ton Suburban
 
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Do they have to be BFG's or Kuhmo's? Are you open to Bridgestones ?Their quality control is top notch,roundness etc.,.I have the A/T REVO very nice... but expensive.
 
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You have to derate the P-series tire load capability by 10% when they are used in a light truck application.

Thus, the actual load capacity of the Kumho P series tire when used on your vehicle is actually about 1826 lbs - lower than the LT tires.

If you like the stock ride, stick with the P series, but only of you can get them in the XL. Looks like the ones you are looking are are not, and I would not downgrade. If you want a firmer ride, then the LT tires will be fine, but will need to run slightly higher pressures than stock. Oftentimes, the LT tires won't carry a treadlife warranty either if that matters.
 
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Read this note from Nitto tire. Shows a lot of information about LT tire and inflation data.

http://www.nittotire.com/assets/safety/Replacing Tires on Light Trucks.pdf

This is probably the most scientific and easy to understand site pointing out the difference in LT and P tires.
Generally, LT tires are constructed to hold weight using HIGH air pressure. Some LT tires can hold 80 psi to carry very high loads. As the web site shows, you run these at too low a pressure at your peril!!!
 
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Originally Posted By: MNgopher
You have to derate the P-series tire load capability by 10% when they are used in a light truck application.


Can you provide a source for this information? I've never seen this recommendation before.
 
I just went through about the same thing, I have a 3/4 ton truck and it came with Michellin Load E tires (121 rated) and I don't haul anything it is never loaded except lawn mower or 4 wheelers so I did not want to go back with Load E tires so I went with the Michelin MS/2 tires in the P series standard tire it is a ( 113 rated ) tire. I looked around and this tire came on the Escalades and expeditions and I think they are heavier than my truck. I may live to regret it if they don"t last. I will get 75,000 at least on my Michelin A/S tires and am hoping for at least 65,000 on the new 'MS/2. These were 144 dollars cheaper than the load E tires. Bought from Discount Tire Direct for 712, free shipping, no tax and got a 70 dollar rebate to mail in for my rebate from Michelin.
 
Quote:
Load Comparison Example, P vs. LT:
P265/75R16 114 Max Load = 2,601 lbs @ 35 PSI
In order to carry the equivalent load, a LT265/75R16 Load Range C must be inflated to 50 PSI. Using this
example, even LT265/75R16 Load Range D, or E must be inflated to 50 PSI to carry the P-metric load at
35 PSI. LT tires do not offer any benefits of being "heavy duty" when under-inflated.


From the Nitto guide.

Quote:
P-Metric Tires on Light Trucks Have Reduced Load Rating:
When a P-metric tire is installed as OE on light trucks, the load rating is reduced by a factor of 1.10 by the
vehicle manufacturer. This load reduction is mandated by Federal Motor Vehicle Safety Standards
(571.120). The reasons for this include the expectation that P-metric tires which are designed mainly for
passenger cars, may experience more severe service on light trucks.
Example - P265/75R16 114S:
Tire and Rim Association Yearbook load tables show 2,601 lbs. Max. Load at 35 PSI. If this tire is fitted to
light trucks however, the load(s) are reduced by a factor of 1.10.
For example: 2,601 lbs. Divided by 1.10 = 2,365 lbs. (rounded) at 35 PSI.
Therefore, if a light truck is fitted with a P-metric tire as O.E., the load at any pressure is reduced by the
1.10 factor. Using this example, a light truck fitted with P265/75R16 114 as O.E., requiring 35 PSI
according to the tire information placard, is actually accommodating a load of 2,365 lbs, not the maximum
load for this size of 2,601 lbs.



Have you checked out the Michelin LTX tires?
 
Oldswagon,

You still haven't told us what the vehicle tire placard says for original tire size. I know there are different versions of the Suburban and some take LT metric and some take P metric.

So which is it?
 
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He didn't say specifically that the placard said this but he did say

Quote:
Stock tires are P235/75-15 XL which actually have a 108 load rating (Kuhmo doesn't make the XL tire).


I'd either find XL tires or upgrade to LT tires.
 
The stock tire on the placard is: P235/75R-15 XL 108S.

I believe this truck left the factory with the above size in Uniroyal Tiger Paws (Ugh..). My summer tires now are BFG Long Trail T/A's, in P metric with the 108 weight rating. I would NOT buy these tires again.

I didn't know that about P-sized tires having a lower weight rating in truck applications. I'll have to do some math and comapare some of the 108 rated P-metric tires.

I have considered Bridgestone Tires, I really like the Revo's, but they are very expensive. I am pretty sure they only come in P-metric but have the 108 weight rating.

I hadn't considered Michlen LTX mainly because Michlens are usually very expensive. Plus, I think the OWL are very unattractive on this tires (I know that's a corny reason, but I like the white letter look). I have a buddy who runs these tires and swears by them, so I might price them out to see how they compare.

I am still unsure which way I am going to go, but I do appreciate all the input, so please contnue to give advice.
 
Check out the LTX at Discount tire direct. I bought a set and the cheapest local price to have installed was 890 $ 3 other places ranged to 970. I got these 4 for a total of 712. then from Discount only they had a 70 dollar rebate which brings me to 640 I can get mounted and balanced for less than 50 dollars. to me this was a great buy. I got the Michelin LTX MS/2 tread wear rating of 720, 70,000 mile tires the load rating is 113, here is the url
http://www.discounttire.com/dtcs/home.do
 
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