tires on 2500HD

Load range 'D' are 8 ply tires...LRD

Load range 'E' are 10 ply tires...LRE

Load range 'C' are 6 ply tires...LRC

There are even higher ply ratings along with their letter designations

The metric number reference the tires sizing....millimeters section width

75 is the aspect ratio in percentage vs 100% tall tire. Ranges from
80 down to 35's the last time I checked

R is a radial construction tire

16 is the tire's wheel dia

OEM tire's recommended tire rim width should be followed when re-engineering
a suspension/tire size. That is also the 'bead to bead' rim width and shady
sales will use the outside of the rim to sell you at a higher price

If the OP's description of it coming with LT245/75R16LRD tires (8 ply tires),
then they are illegal for any GM 2500HD. OEM from GM are LT245/75R16LRE,
a 10 ply tire. In other countries they actually boot a vehicle with
the wrong (lesser than OEM) components, fine the driver and even
fine/revoke/jail the dealer...but sadly not here and why we have such
a mess with too many dealers/customers

This general confusion has RMA (Rubber Manufacturers Association) in the long
process of changing from the 'ply' rating to the generic number code long used
on 'P' (passenger class) tires and most new LT tires today have both load range
coding and soon no more ply ratings (letter coding)

Note going too low PSI on any LT tire (unless floatation LT tires and
only off roading going SLOW) is dangerous as LT tires are NOT designed to be run low

Why 'P' class tires are on most all 'half ton' trucks/SUVs...mainly for ride
quality and they are cheaper than 'LT' class tires of the same OEM/Model/tread/Size. Of course 'half ton' trucks less than 8K GVWR

rhagfo wrote:
Your 2500 should be running 10 ply rating load range E tires, anything less is derating the truck!

Second that. You have to think liability issues as well.

VintageRacer wrote:
If you get a highway comfort tire like the Michelin M/S2 in the LT265/75-16 E-rated size and run them around 45 psi when you are unloaded, you'll get a much more comfortable ride. If you do the shocks it will be better as well. A slightly larger tire has greater load capacity, and a bigger volume of air so it can run slightly lower pressures and have less harshness.

Brian

Me Too ..
LT 265/75 R 16 LRE Michelin highway tires .
I run mine at 50 psi .
for a few bucks more than the stock 245 size I believe i am getting another 10 % in tire mileage and the truck definitely corners better .
i did switch to an 8 inch wide Weld brand aluminum wheel for the 265 be4cause the stock 6.5 inch aluminums are just too narrow , even for the factory 245 tires .

I keep my rear tires aired down on my '09 2500. If I run the recommended 70 psi in them they wear down in the center way too fast and at $250+ each...ouch!

I run them 58-60 psi unless I have to haul something, then I air them up.

Thanks for the replies. I figured everyone was prob running load range E 10 plys on there 2500s.
Yea I have a new pair of NAPA Grande shocks on, but I wish I would have bought Blistens.
Thanks.

If you get a highway comfort tire like the Michelin M/S2 in the LT265/75-16 E-rated size and run them around 45 psi when you are unloaded, you'll get a much more comfortable ride. If you do the shocks it will be better as well. A slightly larger tire has greater load capacity, and a bigger volume of air so it can run slightly lower pressures and have less harshness.

Brian

How old are the shocks? Amazing what a difference a new set of shocks will do for the ride.... ;)

I'm running LT265/75/16 LR E on my F150 and run them at 40 psi and it's a pretty smooth ride.. I also have new shocks..

When I had old shocks and old tires that were LR C and ran them at 40 psi, it was a stiffer/harsher ride than it is now..

Yes, I know I only have a whimpy 150, but so far I am happy with the LR E tires on it..

Mitch

Your 2500 should be running 10 ply rating load range E tires, anything less is derating the truck!

The worst thing I ever did to my last 2500 was put load range D tires on it. Never had problems with trailer sway before that but I sure did afterwards.
I hope yo have better luck than me!