P vs LT

[4WD]

I have always been aware of that but two things.
In this part of the world anyone who tows much buy HD series trucks …
Most that tow with 1500's … are only pulling inshore or bass boats …
(me, and run P275 at 35 psi) …

 

[MNgopher]

Why anyone would own a 1 ton van or truck and even ask about putting P series tires on it is just silly to me, but hey...

Legally, is there a problem? Only if you ever were in an accident where someone was hurt or major property damage is done.

On the common sense side, again, LT tires require higher pressure and stiffer tire construction to carry the same weight. The suspension on the van is tuned assuming this is the case. On a top heavy vehicle, like a van, going with a softer sidewall on a tire seems like it wouldn't be a smart choice where an LT tire was originally specified...

 

[02SE]

Originally Posted by gmctodd
According to TireRack, P rated tires on a light truck are calculated at 91%. A P265/75R16 111T is rated @2403lbs. multiplied by .91 = 2186# each X2 s0 4372#. The GAWR is only 4300#. I know a guy with a 2500 express that switched to p tires on the front, he claims the van rides and handles much better. My question is: As long as I dont exceed the stated capacity of the tire, Is there a legal issue.


The calculated 91% is the 1.1 factor is was talking about. With this new size in question, the tire is wider and about 1" taller. Would it fit in the wheelwell without suspension mods? Is the wheel wide enough to mount the wider section width tire?

As for legality: I am not a lawyer, and therefore would never offer any legal advice.

 

[gaijinnv]

Originally Posted by gmctodd
Have a Express van that has a Front GAWR of 4300lbs. Door sticker calls for Lt245/75R16 @ 50psi, which has a load carrying of 2205lbs. Can I run a P245/75R16 111t with a load index 2403lbs.


Here's what you have:

LT245/75R16 @50psi = Load Limit of 2205lbs

When P-Rated tires are substituted for LT-Rated tires the Load Limit must be increased by a factor of 1.1:

LT-Rated Load Limit = 2205lbs x 1.1 = 2426lbs P-Rated Load Limit

Those tires you asked about never get to the required 2462lbs Load Limit. So, the answer is easy - no, you can not run those P-Metric tires with a Load Limit of 2403lbs.

Note 1: Running P-Metric tires on the front axle and LT-Metric tires on the rear axle is a formula for disaster.

Note 2: GAWR is a secondary consideration. Main determinant of what is required of the tire is what is originally specified for thr tire size and tire pressure on the door placard and the Load Limit of that specification.

HTH

 

[02SE]

Originally Posted by 4WD
I have always been aware of that but two things.
In this part of the world anyone who tows much buy HD series trucks …
Most that tow with 1500's … are only pulling inshore or bass boats …
(me, and run P275 at 35 psi) …


That's great. I have/have had appropriate trucks for their intended use, too.

I was just replying to the OP's specific question.

 

[4WD]

And all ran what they came with or went from P to LT ...
Not backward ...

 

[JLTD]

Originally Posted by gmctodd
According to TireRack, P rated tires on a light truck are calculated at 91%. A P265/75R16 111T is rated @2403lbs. multiplied by .91 = 2186# each X2 s0 4372#. The GAWR is only 4300#. I know a guy with a 2500 express that switched to p tires on the front, he claims the van rides and handles much better. My question is: As long as I dont exceed the stated capacity of the tire, Is there a legal issue.



Probably not. Though a sharp lawyer might cause trouble if there was an accident.