tires on 2500HD

[jbres]

Time to put a new set of tires on my 2007 GMC 2500HD. When I bought the used truck it came with 10 ply load range Ds on it. (LT 245 75 R16) I have to run these tires at 50 PSI or else when I am driving especially empty, the ride is stiff and rough.

Anyone ever ran 8 plys on a 2500HD for a smoother ride? I am towing a 7,000 pound tt max.

If yes, any advice on a nice all terrain type of tire?
I usually run Mastercraft Couser AXT all terrains on my vehicles.

[Norskeman]

My 2004 2500HD came with load range E tires on it - 245's - I swapped them out to 265's load range E. Micheline's.

I would not run load range D tires on a truck used for towing.

[jbres]

thanks for all the tips and advice! much appreciated!

[Redsky]

I get more benefit from putting an extra 200 lbs. of weight in the bed when not towing than from deflating the tires. I ran with the tires for 5k miles based on the load and the tire manufacturer's chart and I saw that if I continued with the lower air pressures I was going to lose about 20% of the tire life.

Now I run with the tires at the PSI shown in the plate on the door frame and all is well in terms of handling and tire wear. It is a 3/4 ton truck and for a smooth ride as a priority I would have stuck with Toyota 1/2 ton mini trucks with their independent front suspension. No way to get a car like ride with a solid front axle.

[mtofell1]

fwiw.... any tire shop with a clue about liability will not install anything that de-rates the truck.

You can play around with shocks and tires but nothing will really make that much of a difference with a 3/4 ton truck. If you really want a soft ride like in a 1/2 or passenger car get air suspension.

My buddy's 2500 came with that and it was amazing. The thing rode like a Cadillac. If/when you need to haul some weight you just push a button on the dash and pump it up.

The 2014 Dodge trucks are coming out with this for the rear end and it should make a big difference. The harsh ride on 3/4 ton trucks is just a fact of life. You can't have a suspension capable of carrying a lot of weight and have a smooth ride at the same time.

[Cummins12V98]

There is a thing called a load/inflation chart for every tire out there. Use it based on actual load and your ride will improve as well as your tire life.

[jadatis]

To be shure you should calculate the needed pressure with use of spreadsheet I made.
Even P-tires can be enaug for the loads to carry, but calculating makes it shure.
Only advantage is that a 10PR/E-load tires makes the sideward swaying less with the same deflection so comfort and stiffer together.
If you want to do that with a P-tire you need that high pressure, that the deflection of it gets that less that comfort gets bad.

But a E load tire needs a higher pressure for the same load on it, then a P-tire. How much more you have to calculate.

Here the link to a map on my skydrive wich belongs to my hotmail.com adress with same username as here.
Motorhome tire-pressure calculator

In this map CLICK RIGHTand choose DOWNLOADfrom the dropdown-box to download it first to your computer. Other means go wrong, like leftclicking or "open in WEB-APP", or are to complicated like "open in EXCELL" wich asks to log in with your hotmail adress.

After download open in Excell or Open Office Calc on your computer.

What you need at minimum is maximum load of tires and pressure needed for that ( E-load 80 psi) and preferably weighed wheel/pair or axle-loads of vehicle. In lack of that the GAWR's are used if given, with a reserve that I think is needed, but you can give your own reserves.

Here a picture of a filled in calculator to show what you can do with it.

[BenK]

This discussion, as any tire/suspension re-engineering discussion involves the
laws of physics and until one can speak to how these re-engineering changes affect
"Slip angle, bend back, roll over, roll resistance, response times, etc", then
stick with OEM and if must go to different spec tires, stick to the OEM (vehicle,
tire, and wheel) specifications and recommendations

Stuff like 'slip angle' of a tire can be changed just by the PSI it is aired to.
Or the rim width it mounted on. Or the dampening system (mainly shocks) involved
plus a host of other attributes that all play together in concert between the vehicle and pavement

Folks like Marty are a real time test mules for any vehicle and associated components/systems

Betch he can't remember how many sets of tires he's owned and burned through...except
for the ones which failed miserably for him, as someone else might love that
particular tire for 'them'. I no longer like Michelin LT tires, as
they cracked on me...many sets while many love them.

Also, betch most won't notice a change in slip angle from one set of tires to another
set on their vehicles
Or the responsiveness from one set to another

Not a knock on folks, but that is the generality of re-engineering to non-techies
who take things in absolute terms

Like tire pressure....50 PSI for instance

out of context if the tire class isn't mentioned, the rim width in reference to
the recommended for 'that' thire, the loading, the dampening rate of the shocks,
the terrain, and the drivers style of driving

'P' class tires are designed to have lots of sidewall bend back for 'ride quality'

'LT' class tires are designed to have less sidewall bend back for 'truck' attributes
Mainly load carrying

My 1980 C10 Silverado's LT class tires are 6 ply (load range C) and have a
max PSI specification of 35 PSI. If I ran my LT265/75R16E's on 10" wide rims at 35PSI
they might come off the bead and over heat hat highway speeds

50 PSI in them would have them over inflated and over stressed to possibly break
ply or tread cords when it impacts road object.

50 PSI in my LT265/75R16E's would be a bit low for my driving style, but would
be fine for the load when empty. But not for my driving style. Harsh is kind
as am still a boy racer at heart in my 60's.

I'll never recommend going below 45 PSI for any LT class tire...unless
they are off roading and crawling below 20mph

Scary for me to see advice out of context and OPs accepting advice out of context

Like I run 80 PSI in all four on my Suburban, but then it would be too harsh
for most folks out there. How many have 10" wide rims, bead to bead ? Not
many and those who do, either had the salesperson sell them or they knew what
they were getting into when they bought them...

Why the advice to use load charts sound. As tires are mainly air bladders holding
up weight with additional duties: Steering/cornering/stopping/accelerating
and of course shock absorbers. Plus knowing the weight on each axle...how
else would anyone know how to find the right PSI on any OEM's inflation charts?

[blt2ski]

I'm runnign 50 lbs on my reg cab 2500 all around, except when loaded. My old SW CC K3500, with 265 16 rubber, I was 50-55 for the front, ie a diesel vs a 350 SB V8..... another 800 lbs on the fa. REAR was 45 or so when empty. Found no difference in ride quality with the 265's towing or other wise with D tires vs E, other than 3000 lbs of tire vs 3400. THe 265's in a D range were 40 lbs less than a LR E 245-16. With 7.5" rims, I found the D rated 265;s to handle loads better than the 245's, both of these handled loads better than an LRE 235-85 16. The width seems to be the key.

Marty

[KD4UPL]

Why do you "have to run 50 psi" even empty?
Have you consulted a tire load inflation chart for your tires. I would bet that with the truck empty you could safely run lower pressure.
I would put E tires on a 2500HD truck. I would only run as much pressure as the load calls for.

[Curly2001]

Michelin are overrated in wear. Will try Firestone Transforce next round. Will go E rating as I have with Michelin but hope to get more than 35K out of them.
Curly

[BenK]

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

[tegu69]

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.

[Lowsuv]

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 .

[NJRVer]

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.