More tire pressure info please

Gcappy56

New member
Apr 5, 2023
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Just got my 3500 SRW with 18” stock tires. I run empty most of the time. I don't think 80 psi will be good empty. I saw an old thread but almost everyone is running larger tires. What pressure’s do you guy’s run on your 3500 SRW when empty?
Thank’s
 

660catman

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May 18, 2021
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Not a 3500 but I run my 2500HD Duramax with 18” Michelin LTX AT2’s at 60 front and around 58 rear. I tried to go lower but the TPMS light comes on. I found out you can get it programmed to a lower PSI before light comes on.


2013 Sierra SLE 2500HD Crew Cab
 
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2004LB7

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I take the weight rating of the tire at it's max pressure and divide the weight by the psi. Then multiply that by the weight on each tire. That gets you close and can adjust from there

For my truck. Front is about 4500 lbs. That's 2250 lbs on each tire. My tires are rated at 3750 lbs at 80 psi. 3750/80 = 47 lbs per psi. 2250 lbs / 47 = 48 psi in each tire.

Rear is something like 3500 lbs. Since mine is a DRW that would be 875 lbs per tire. That works out to about 19 psi per tire

I think in the end I settled on 45 psi in the front and 25 in the rear.

Adjust for your tires rating, vehicle weight, tire wear and handling, etc. I think for most SWD vehicles with lower rated tires will come out close to what Tom uses
 
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SoCalMike

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Dec 12, 2010
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I use a website called tire size.com to see what tire pressures to run. I'm on 35x12.5r17 and run 34 front 30 rear.

Sent from my SM-G996U using Tapatalk
 
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Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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you wont be able to change the TPMS warnings in that truck without a MDI2 and the dealers will not do it for you. i need to try flashing mine and see if it will actually take for a "P" rated tire. then you can go down to 25psi before the light turns on. you can only go down to 55ish psi before it will throw a warning light for tire pressure as of now. i use to run mine at 60psi but with the change in outsite temps, i swore it was like ever month i was having to add a little air to keep the light off. now i run 65 front and 75 rear and dont have to play with pressures. i noticed no difference in rear end ride between the pressures when unloaded. My truck is a CC/LB 2500 SRW with factory 20" wheels. i ditched my methods and 35's about 2 years ago.
 

Gcappy56

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Apr 5, 2023
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Well today I checked all pressures. The fronts are at 59, I left them there. The rear’s were at 50, I set them to 45. Took a drive into town, no warning lights. I guess I’m ok.
The first owner must have reduced pressures.
 
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2004LB7

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I'm pretty sure the newer models have it. Maybe starting with the LML? I know my 08 doesn't
 

Gcappy56

New member
Apr 5, 2023
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3
Ny
you wont be able to change the TPMS warnings in that truck without a MDI2 and the dealers will not do it for you. i need to try flashing mine and see if it will actually take for a "P" rated tire. then you can go down to 25psi before the light turns on. you can only go down to 55ish psi before it will throw a warning light for tire pressure as of now. i use to run mine at 60psi but with the change in outsite temps, i swore it was like ever month i was having to add a little air to keep the light off. now i run 65 front and 75 rear and dont have to play with pressures. i noticed no difference in rear end ride between the pressures when unloaded. My truck is a CC/LB 2500 SRW with factory 20" wheels. i ditched my methods and 35's about 2 years ago.
Thanks, after some investigating I found the D.I.C was reading the tire pressures backwards. I made the dealer rotate the tires when I bought the truck and it seems they did not re-learn the tire position. I bought a learn tool and did it myself. Strange though, after the re-learn my D.I.C is warning me of low rear tire pressures. It did not do that until I did the re-learn. I will take the back tires back to 50 where I found them and see if the warning goes away.