Ram 2500 Tire Pressure?

[CedarCreekWoody]

I just bought a new Ram 2500 4x4 diesel (yay!) Tires had 85 lbs PSI from the dealer which they said was correct. But the door post sticker shows 60 PSI for all tires. Max pressure per the tire sidewall is 80 PSI (load range E). I have lowered them to 80 currently.

So these are my questions:
What PSI for everyday driving?
What PSI when towing?
When towing on highway should front and rear be the same pressure?

I am currently towing a bumper pull at 7,700 lbs, planning soon to be towing a fifth wheel in the 10-11k range.

[wanderingbob]

I have the same truck and run 75 in rear and front . I would go with what it sez on the sidewall of tire ! There is no reason that front and back must be the same , When using truck and not towing I might go down to 65 for a better ride . Sidewall , sidewall , door post does not know what kinda tire you are wearing !

[CedarCreekWoody]

Thanks. That is in line with my thinking too.

[Kimber45]

Originally Posted by wanderingbob

I have the same truck and run 75 in rear and front . I would go with what it sez on the sidewall of tire ! There is no reason that front and back must be the same , When using truck and not towing I might go down to 65 for a better ride . Sidewall , sidewall , door post does not know what kinda tire you are wearing !

It does if they are OEM tires

[CedarCreekWoody]

Originally Posted by Kimber45

It does if they are OEM tires

And they are.

[upflying]

You might get a TPMS light if you lower the pressure.

[CedarCreekWoody]

Originally Posted by upflying

You might get a TPMS light if you lower the pressure.

That is built into the truck. The question is what pressure to run in them.

[MR.M]

Originally Posted by CedarCreekWoody

I just bought a new Ram 2500 4x4 diesel (yay!) Tires had 85 lbs PSI from the dealer which they said was correct. But the door post sticker shows 60 PSI for all tires. Max pressure per the tire sidewall is 80 PSI (load range E). I have lowered them to 80 currently.

So these are my questions:
What PSI for everyday driving?
What PSI when towing?
When towing on highway should front and rear be the same pressure?

I am currently towing a bumper pull at 7,700 lbs, planning soon to be towing a fifth wheel in the 10-11k range.

It all depends on weight . with the diesel i would assume a higher front tire PSI . if bed is empty and not towing then i would assume a lower PSI . the 85psi that you got was that clod are were the tires still hot from driving . if they were hot then 85 was fine . all settings are at cold psi . i run 70 to 75 not towing and when towing i keep fronts the same the up the rears to 80.

[frank4711]

I run 63 all 4 ... gives me plenty of load coverage and best ride ... more than I would ever need for current set up ... I will check wear at first rotation ...

[CedarCreekWoody]

Originally Posted by MR.M

It all depends on weight . with the diesel i would assume a higher front tire PSI . if bed is empty and not towing then i would assume a lower PSI . the 85psi that you got was that clod are were the tires still hot from driving . if they were hot then 85 was fine . all settings are at cold psi . i run 70 to 75 not towing and when towing i keep fronts the same the up the rears to 80.

The 85 reading was cold. I dropped them to 80 but I'm leaning toward the same opinion as you (70 to 75 normally, rear at 80 when towing.)

[frank4711]

Get your weights when you can and you can dial it in and cover the load ... I am at 3100 lbs per tire at 63 psi

[MR.M]

Originally Posted by CedarCreekWoody

The 85 reading was cold. I dropped them to 80 but I'm leaning toward the same opinion as you (70 to 75 normally, rear at 80 when towing.)

I know the chevy drives nice at those ranges so no need to go lower and tire wear at least on my old chevy never showed signs of over inflated and will assume it will be the same with the new chevy . the highr psi you can run empty and get good tire wear the better mpg you will get also .

[CedarCreekWoody]

Originally Posted by frank4711

Get your weights when you can and you can dial it in and cover the load ... I am at 3100 lbs per tire at 63 psi

Good info Frank. What chart did you use to determine the PSI for the various weights?

[cfo111]

I my self would do what the data plate on door seal says company who built truck should know what PSI is needed in the tires. After all the company built it from the ground up and know what suspension is there and what is needed.

[frank4711]

Originally Posted by CedarCreekWoody

Good info Frank. What chart did you use to determine the PSI for the various weights?

https://commercial.firestone.com/con...s_web_2014.pdf .... Page 6 .... LT275 R70 18 ... at 63 psi about 3100 lbs ... Congrats on the truck .... Thanks OEM FIRESTONE
TRANSFORCE HT
Highway All-Season
Size: LT275/70R18 125/122S E
Style: Blackwall
Load Range: E
Serv. Desc: 125/122S

[CedarCreekWoody]

Originally Posted by frank4711

https://commercial.firestone.com/con...s_web_2014.pdf .... Page 6 .... LT275 R70 18 ... at 63 psi about 3100 lbs ... Congrats on the truck .... Thanks OEM FIRESTONE
TRANSFORCE HT
Highway All-Season
Size: LT275/70R18 125/122S E
Style: Blackwall
Load Range: E
Serv. Desc: 125/122S

Thanks Frank, that is exactly the info that I needed! My axles are rated at 6,000 each, putting it at 60 psi which is what the manufacturer recommends. Once i get my new camper i will put it on the scales to fine tune it.

[ard58]

Originally Posted by wanderingbob

I have the same truck and run 75 in rear and front . I would go with what it sez on the sidewall of tire ! There is no reason that front and back must be the same , When using truck and not towing I might go down to 65 for a better ride . Sidewall , sidewall , door post does not know what kinda tire you are wearing !

True, the door post does not know, but the ecm does. I have a 2017 F250 and lowered my pressures, about 10 psi, for a better ride. After awhile started getting the TPWS light. Went to tire store and they said if you want to run lower pressures you need to go to dealer and have them adjust what pressures are currently in the vehicle computer. Otherwise, run whats on the sticker.

[primo20]

My 17 Ram door sticker listed different pressures for front and rear tires. 60 front 80 rear.

I ran all 4 at 80 when towing.

[Mountndream]

x2

[TowPro]

Or you can use math.

LT215/85R16 LRE weight stamp on sidewall = 3650 lbs @ 80psi per tire.

If we take 3650 lbs divided by 80psi = 45.625 lbs per 1 PSI

Now your weight tickets show loaded truck weighs 4920 lbs spread across 2 tires, so we are really only carrying 2460 lbs per tire.

Take 2460 divided by 45.625 Lbs per PSI and we see it works out to 53.9 PSI. So I would run 60psi COLD.


Not sure which model you have, but your GVWR is probably 6000 lbs.
3000 per tire devided by 45.625 lbs per psi = 66 psi. I would expect your tire card to say 65psi on rear but you might have tires/rims that were are options.


this calculation will also work for front pressure

But your 2500 is GVWR of 10,000 or less. (I did not add up your front and back weight see how much you weigh ) and the TMPS system will not let you lower the tires below something like 62psi without an alarm.

The 3500's are over 10K so they have a different TPMS system where you can set the tire to any PSI but you don't get an alarm when they go flat.
(I used to run 35psi in back of my dually empty)