Tire Pressure Using 8-ply (load Range D) Tires

[t-go]

I've currerntly got the stock LT245/75/16 10-ply tires(load range E) on with 65psi (front) and 80psi (rear).

I'm changing to LT265/75/16 8-ply tires (load range D) and was wondering if anyone has this setup on a 2500HD?

If so, wondering what you run for tire pressures in this scenario? The side of the door only shows pressures for the stock tires (same as the owners manual).

 

Max pressure of the 10-ply tires is 80psi and GM recommends the following for the stock tires:

65psi front

80psi rear

The fronts are set to approx 81% of the max pressure.

 

If I were to follow the logic with the 8-ply tires that have a max pressure of 65psi:

53psi front

65psi rear

 

Anyone running the 8-plys on their 2500HD? I don't "need" the 10-ply tires for what I'm using the truck for.

Specifically, my truck is a 2006 GMC 2500HD ext-cab 4wd.

 

[Matt_]

Does your door tab or owners manual specify loaded & unloaded tire pressures?

 

I remember seeing these... though i dont remember if it was on a GM vehicle..

 

It was something along the lines of:

Unloaded: 50 front / 50 rear

Loaded: 65 front / 80 rear

 

I'd check to see if your owners manual has something similar specifed... and if it does, just go with the 'unloaded' pressures and if you're going to be hauling a heavy load, fill the tires to the max on the sidewall...

[t-go]

Believe it not, the owners manual shows nothing about what to set them at...(kinda funny too, given the title of the section is "Inflation-Tire Pressure":

 

Inflation - Tire Pressure

 

 

Tires need the correct amount of air pressure to operate

 

 

 

effectively.

 

 

Notice: Do not let anyone tell you that

 

 

 

under-inflation or over-inflation is all right. It is not.

 

 

 

If your tires do not have enough air (under-inflation),

 

 

 

you can get the following:

 

 

• Too much flexing

 

 

• Too much heat

 

 

• Tire overloading

 

 

• Premature or irregular wear

 

 

• Poor handling

 

 

• Reduced fuel economy

 

 

 

If your tires have too much air (over-inflation),

 

 

 

you can get the following:

 

 

• Unusual wear

 

 

• Poor handling

 

 

• Rough ride

 

 

• Needless damage from road hazards

 

 

A Tire and Loading Information label is attached to the

 

 

 

vehicle's center pillar (B-pillar), below the driver's

 

 

 

door lock post (striker). This label lists your vehicle's

 

 

 

original equipment tires and their recommended cold tire

 

 

 

inflation pressures. The recommended cold tire

 

 

 

inflation pressure, shown on the label, is the minimum

 

 

 

amount of air pressure needed to support your vehicle's

 

 

 

maximum load carrying capacity.

 

 

 

For additional information regarding how much weight

 

 

 

your vehicle can carry, and an example of the tire

 

 

 

and loading information label, see Loading Your Vehicle

 

 

 

on page 4-48.

 

 

Funny, even the referenced page 4-48 shows nothing...

 

I double-checked the driver door and nothing with respect to loaded/unloaded. I would have "expected" that to be there as well...weird.

Also, I stand corrected on the 10-ply recommended inflations...should be 55psi front 80psi rear based on my driver door for the stock LT245/75/16 tires 10-ply tires.

 

Hoping someone can help "crack the code".

 

I 'spose I can always run down and ask the dealer too. But wanted to see what real people are doing.

[Matt_]

if your current door sticker says 55 front / 80 rear... then run 55 front and rear with your new tires and bump the back ones up to max (65?) when towing/hauling a heavy load.

 

There's no reason why the bed of the truck should have more pressure than the front of the truck when you're not hauling anything...

[brims]

They really should have a pressure for both loaded and unloaded on all trucks. On the 1500 the center of the tread on the rears wears fast at the factory pressure.

[Roofer]

On my Ram it states a pressure for loaded and unloaded.

 

On the 2500HD I had D rated 265's. I ran them at 50PSI all around unless I towed or hauled something that was close or above the trucks capacities. Then I would bump the rears up to 65.

 

If you go with BFG KO's, don't worry about the D rating over the E rating. They have a triple ply sidewall and are very tough. I had more weight on 265 D rated, than most will ever have on their E rated tires.

[t-go]

Thanks guys. Yeh, didn't make sense for my rears to be maxed out with nothing in the bed.

 

Hey Roofer, I went through 2 sets BFG KO's on my previous truck (99 Ram 1500) and also were 265's D rating. Agreed, those tires are really tough and they definitely look bada$$. I'd buy them again, but the sipes aren't as good as I'd like for snow/rain and highway and they were a little noiser than I'd like right now. I'm currently looking at the Michelins LTX M/S (but those aren't avail in D), so been researching the Yokohama Geolander A/T-S which I can get in the D rating and I've seen good reviews on them via tirerack, etc.

[Roofer]

I can't comment on either on of those, but the Michelins have gotten very good reviews here that I have seen.

[sonjaab]

Simple.........If you switched to NON stock tires just follow the tire mfrs.

inflation pressure guidelines printed ON the side of the tire !

[Mike2500HD]

I've currerntly got the stock LT245/75/16 10-ply tires(load range E) on with 65psi (front) and 80psi (rear).

I'm changing to LT265/75/16 8-ply tires (load range D) and was wondering if anyone has this setup on a 2500HD?

If so, wondering what you run for tire pressures in this scenario? The side of the door only shows pressures for the stock tires (same as the owners manual).

 

Max pressure of the 10-ply tires is 80psi and GM recommends the following for the stock tires:

65psi front

80psi rear

The fronts are set to approx 81% of the max pressure.

 

If I were to follow the logic with the 8-ply tires that have a max pressure of 65psi:

53psi front

65psi rear

 

Anyone running the 8-plys on their 2500HD? I don't "need" the 10-ply tires for what I'm using the truck for.

Specifically, my truck is a 2006 GMC 2500HD ext-cab 4wd.

 

Ignore what it says on the door if your running non spec tires. Make sure the load rating on the tires is sufficient and run the pressure based on load and what it says on the tire. The door info is irrelevant.

[TnRedneck]

Simple.........If you switched to NON stock tires just follow the tire mfrs.

inflation pressure guidelines printed ON the side of the tire !

 

The pressures shown on the tire's sidewall are prebably NOT the pressures for your vehicle. The pressures listed on the sidewall of the tire are the maximun correct air pressure for the maximum load also printed on the sidewall. You probably do not operate your truck at these maximum loads. (If you do- then the tire sidewall is the maximum and is correct.)

 

Vehicle manufacturers have a separate placard on the vehicle for what they consider the correct air pressures for ride, load, handling, etc. When you are in doubt, have your truck weighed loaded and unloaded (by axle or [even better] by axle end) and call the tire manufacture. They will look in the Tire & Rim Association's yearbook for the correct inflation pressure.

[2COR517]

245 Load Range E and 265 Load Range D both are rated for the same weight capacity, 3042 lbs. Different PSI though. 80 for the 245, 65 for the 265. If you run your tires at the psi on the sidewall, and you're empty, or not at the max weight, a couple things will happen. Truck will ride like crap, and handle poorly. And the center of your tires will wear out long before the edges. The PSI in the door jamb are based on the Gross Axle Weigh RATINGS (GAWR) assigned by GM. You're not at that weight either, so forget those numbers too.

 

The best way to set your tire pressure is to weigh your truck, each axle separately. Scales are available at gravel pits, transfer stations, truck stops, etc. MIght cost you ten bucks, but worth it. Those tires are almost a grand. Then you can e-mail BFG for a PSI/weight table for your tire. You are going to be very surprised at how low you should be. My truck weighs almost 6000 empty. 3500 front, 2500 rear. I have BFG ATs on, 31/10.50/16.5. They are Load Range D. 2745 lbs at 65 PSI. According to the info directly from BFG, I should be 35 PSI all the way around. Actually less for the rear, but they do not recommend running 16.5s below 35 PSI because the beads do not lock in the rims like 16s. I have the fronts at 40, rears at 35. I have been running my tires at these pressures for more that three years. Truck rides much better, handles better, and tires wear very evenly. Of course, I air up for heavy loads and towing.

 

Here is the data they sent me. Remember, these are single tire values, "half" your axle weight.

Thank you for your email. We welcome the opportunity to serve you. Please

see the table below.

 

1830-35 2000-40 2165-45 2320-50 2465-55 2605-60 2745-65

 

The first number is pounds and the second is the PSI.

 

Here is a chart from Goodyear. Most of us have tire sizes on page seven. It's not very complete for bigger sizes, but you can e-mail your tire manufacturer. BFG responded in less than a day.

 

http://www.goodyear.com/truck/pdf/databook/loadInflation.pdf

[davzog]

I have 265x70x17s in my HD, load range "E"....I run 50 pounds in the front and 45 in the rear unloaded....jack the whole set up to 80 loaded.

 

After two years, I have found this the truck rides better unloaded and the tires wear straight across the tread....and I rotate them every 6-7,000 miles.

[plowking]

I have 245-75-16 Bridgestone tires[ stock]. I had the rear tires deflated to seventy pounds. It seemed to help ,even when towing. At eighty pounds I would get wheelspin,tire chatter on gravel or going from gravel to tar. Much better now,it will still spin them bad in the rain on takeoff,so I just roll into the throttle. plowking

[yukon25008.1]

The tire guy i use always says(max pressure) but i never do, i would think w/no load at max pressure the would wear bad in the center.