Tires on 2020 RAM 2500

[Chief Brown]

I recently purchased a 2020 RAM 2500 Big Horn. The door placard says run 60# air in tires. The cold tire pressure is 80# on side of tire. My fiver is 10,200 dry weight. So trying to determine where should I set the tire pressures? What do you guys think?

[CADman_KS]

Originally Posted by Chief Brown

I recently purchased a 2020 RAM 2500 Big Horn. The door placard says run 60# air in tires. The cold tire pressure is 80# on side of tire. My fiver is 10,200 dry weight. So trying to determine where should I set the tire pressures? What do you guys think?

Our old 5er was that weight, and I ran 80 in the back, and 60 in the fronts loaded.

Unloaded, I would typically put them down to 45-50...

[jimcol]

Originally Posted by CADman_KS

Our old 5er was that weight, and I ran 80 in the back, and 60 in the fronts loaded.

Unloaded, I would typically put them down to 45-50...

Like you I ran the unloaded PSI recommendation when empty so as to soften the ride. It softened the ride but ate the tires. Michelin adjusted two replacement sets for me but said no more. So now I ride around at the loaded rate recommendations and struggle to keep the fillings in my teeth. But on a side note the tires seem to be wearing better.

[Montana Man]

Lkie CADman said.

[1retired06]

Originally Posted by jimcol

Like you I ran the unloaded PSI recommendation when empty so as to soften the ride. It softened the ride but ate the tires. Michelin adjusted two replacement sets for me but said no more. So now I ride around at the loaded rate recommendations and struggle to keep the fillings in my teeth. But on a side note the tires seem to be wearing better.

Same here. 80PSI is the routine for me.

[CADman_KS]

Originally Posted by jimcol

Like you I ran the unloaded PSI recommendation when empty so as to soften the ride. It softened the ride but ate the tires. Michelin adjusted two replacement sets for me but said no more. So now I ride around at the loaded rate recommendations and struggle to keep the fillings in my teeth. But on a side note the tires seem to be wearing better.

I have never really noticed any issues running a little bit lower than recommended unloaded, but that I could understand how that might be an issue.

I can definitely tell, though, when I lower the pressure in them. 80PSI is the equivalent to steel wheels...

[Chief Brown]

So did you run 45# in rear unloaded?

[CADman_KS]

Originally Posted by Chief Brown

So did you run 45# in rear unloaded?

Yes, I did. Between 45-50, fronts and backs unloaded. I never have had anything in the back of my truck that comes close to the pin weight of the 5er, so it was never a big deal.

Again, I couldn't tell any difference in tire wear at that pressure, either, so that's what I ran...

[CADman_KS]

We have a 2020 Chevy now, with TPMS, and I believe that the default TPMS setting is 50 or 55. I need to look at that, and see what it is. I'm pretty sure that it's lower than what the door sticker says.

I'll check when I get home...

[mlh]

The 60 pound gives you the weight rating of the truck 80 is the max for the tires. When pulling your camper run the rear tires at 80. They will be more stable and carry all the weight they are rated for.
Lynwood

[jsb5717]

Interesting, the placard in my 2012 RAM says 75 rear and 60 front. That's where I've run them

[PSFORD99]

Originally Posted by jsb5717

Interesting, the placard in my 2012 RAM says 75 rear and 60 front. That's where I've run them

My 2014 Ram 3500 80 rear 60 front on the door placard . I leave the front 60 all the time ,run the rears 45 empty ,80 towing the fifth wheel. It seems the rough ride is coming from the rear empty ,and 45 solves most of the rough ride .

[PSFORD99]

Originally Posted by CADman_KS

We have a 2020 Chevy now, with TPMS, and I believe that the default TPMS setting is 50 or 55. I need to look at that, and see what it is. I'm pretty sure that it's lower than what the door sticker says.

I'll check when I get home...

No default on the Ram 3500's run what you like ,yet the 2500 Rams have the default . I do have the screen to read air pressures .

[sourdough]

My 14 Ram 2500 had 65F/80R posted on the door and the current 3500 does as well. Size is 285/60 20. I keep the fronts at 65 and run 60-65 in the rear when unloaded.

[CalandLinda]

It's a question often discussed here. For me, the answer is always the same. The correct inflation pressures for your OE tires is what has been recommended by the vehicle manufacturer. The vehicle manufacturer's recommended cold inflation pressures are depicted on the vehicle certification label, tire and load label and in the vehicle owner's manual. Unless; there is optional/supplemental recommendations from the vehicle manufacturer.

That statement or one like it will be found in every reference you ask for when hunting for your vehicle's correct inflation pressures.

Optional inflation pressures between vehicle manufacturer cold recommendations and tire sidewall maximums is at the discretion of the consumer.

The USTMA supports the vehicle manufacturer's recommendations by stating that your tire inflations should NEVER be lower than what has been recommended by the vehicle manufacturer.

NOTE: The tire manufacturer will list, on the tire sidewall, the maximum permissible inflation pressure needed for that tire to provide its maximum load capacity. It's not a recommendation. It's intended to be informational.

[PSFORD99]

Originally Posted by sourdough

My 14 Ram 2500 had 65F/80R posted on the door and the current 3500 does as well. Size is 285/60 20. I keep the fronts at 65 and run 60-65 in the rear when unloaded.

My 2014 Ram tires are the LT275/70/18 E rated ,as said mine are 60/80, but with that 3500 40-45 works best unloaded in the rear . It appears 80 is max on most of these E rated LT tire 16-20" . I have yet to buy an LT E rated tire that hasn't been 80 psi max weight rating ,this goes back to my early 99 Superduty . Bought new in July 98

[PSFORD99]

Originally Posted by CalandLinda

It's a question often discussed here. For me, the answer is always the same. The correct inflation pressures for your OE tires is what has been recommended by the vehicle manufacturer. The vehicle manufacturer's recommended cold inflation pressures are depicted on the vehicle certification label, tire and load label and in the vehicle owner's manual. Unless; there is optional/supplemental recommendations from the vehicle manufacturer.

That statement or one like it will be found in every reference you ask for when hunting for your vehicle's correct inflation pressures.

Optional inflation pressures between vehicle manufacturer cold recommendations and tire sidewall maximums is at the discretion of the consumer.

The USTMA supports the vehicle manufacturer's recommendations by stating that your tire inflations should NEVER be lower than what has been recommended by the vehicle manufacturer.

NOTE: The tire manufacturer will list, on the tire sidewall, the maximum permissible inflation pressure needed for that tire to provide its maximum load capacity. It's not a recommendation. It's intended to be informational.

I know a lot of guys towing fifth wheels, and when we talk about these tires ,and inflation etc etc , to the man ,they all run max tire inflation towing their trailers ,and nearly all air down when running empty . I have been since I first started towing fifth wheels .

[kowbra]

Originally Posted by CalandLinda

It's a question often discussed here. For me, the answer is always the same. The correct inflation pressures for your OE tires is what has been recommended by the vehicle manufacturer. The vehicle manufacturer's recommended cold inflation pressures are depicted on the vehicle certification label, tire and load label and in the vehicle owner's manual. Unless; there is optional/supplemental recommendations from the vehicle manufacturer.

That statement or one like it will be found in every reference you ask for when hunting for your vehicle's correct inflation pressures.

Optional inflation pressures between vehicle manufacturer cold recommendations and tire sidewall maximums is at the discretion of the consumer.

The USTMA supports the vehicle manufacturer's recommendations by stating that your tire inflations should NEVER be lower than what has been recommended by the vehicle manufacturer.

NOTE: The tire manufacturer will list, on the tire sidewall, the maximum permissible inflation pressure needed for that tire to provide its maximum load capacity. It's not a recommendation. It's intended to be informational.

While completely correct and I agree with the recommendations, I'll provide alternative data for consideration.

First note that the manufacturers recommended MAX pressure is to support the manufacturers rated MAX load. IOW, you cannot safely achieve rated GVWR with less than the manufacturers recommended tire pressure.

However, heavy duty pickup trucks are also extremely variable in their weights compared to other classes of vehicle on the road. Commercial work trucks run loaded almost all the time, so they run recommended max pressure every day, no question. On the opposite side, cars often have only a few hundred pounds of difference between empty and loaded, so MAX pressure also works good; it supports the weight and conveys a smooth ride whether empty or loaded.

Compare the above to the HD pickup, especially the rear axle. For a 3500 class vehicle, the rear axle weight could vary by as much as 4000lbs or more during typical driving conditions -empty vs loaded. What tire pressure would be adequate for empty weights vs loaded weights? We don't have to guess, those ratings are published.
The OP didn't provide tire size, but PSFORD99 provided his tire size at LT275/70R18.
https://tirepressure.com/lt275-70r18-tire-pressure

Based on the tire pressure chart, and given that PSFORD99s 2014 RAM 3500 has a 6000lb front axle and a 7000lb rear axle, you can see why the manufacturer has recommended 65psi front and 80psi rear.

To determine what might be a safe empty tire pressure, lookup the information for the truck, in this case,
http://www.rambodybuilder.com/2014/d...ammlup3500.pdf

Assuming the most popular RAM, a Laramie cummins crew cab short box 4x4, the empty axle weights are; ~4800lbs front axle and ~3000lbs rear.

Back to the tire charts and you could see that empty the rear axle is so light that even 35psi would technically work; and the front axle, empty, could go as low as 40psi. But at those pressures most LT tires would feel very squirmy and have poor wear.

What's the point of the above? There is a bit of art meets science here. If you are loaded, use the max tire pressure recommended by the manufacturer on the door sticker (not the max on the sidewall).
But, if driving empty, you can easily lower tire pressure by a considerable amount and still safely carry the load. The limiting factors then become how does the tire feel and how does it wear?
Most LT tires will feel ok at 55psi, and some feel ok below that.

Then, if you want to check on wear, air the tires to where it feels good empty, and do a chalk test. Put a thick chalk line across the tire, drive ahead on dry pavement and see where the chalk makes contact. If even across the tire, then the pressure will be fine.

Again, I completely understand that the "correct" answer is to follow the stated manufacturers recommendations. But running tires at 80psi to support a 7000lb axle load then only loading them at 3000lbs, will not provide a smooth ride. So if you want a nicer ride empty, the above provides an example of research to support doing that safely.

Just make sure to air back up when loading up.

hth

Brad

[Fish]

I'm not going to take the time to air up and air down my tires on my dually. I run them at max cold pressure all the time.

I don't have a problem with the ride comfort. maybe it's because I have the factory air bags.

The tires that Ram put on my 3500 from the factory are junk. Nexens. I just slipped a belt in one of the front ones the other day and had to put new front tires on. I thought it was going to shake the front of the truck off before I got back to the campground.

[kowbra]

Originally Posted by Fish

I'm not going to take the time to air up and air down my tires on my dually. I run them at max cold pressure all the time.

I don't have a problem with the ride comfort. maybe it's because I have the factory air bags.

The tires that Ram put on my 3500 from the factory are junk. Nexens. I just slipped a belt in one of the front ones the other day and had to put new front tires on. I thought it was going to shake the front of the truck off before I got back to the campground.

Sorry to hear of your issues, and I've heard others have had similar poor results. The RAM SRW trucks all seem to come with Firestone Transforce tires. While reasonably long wearing, they really are poor in wet or snow. I changed mine out right away on this truck. I think the poor quality factory tires is RAMs biggest shortfall compared to the competition.

I agree with not airing up and down on a dually. I didn't do it either as it doesn't make enough of a difference and a pain to do it.

On the SRW trucks, especially the 350/3500 class? Totally different story and airing down when empty on the rear tires does make a huge difference in ride quality. (I also have a RAM 3500 with factory rear air suspension, but SRW this time. While a nicer ride than older models, less air when empty dramatically improves ride quality).


Brad