How to deal with tire pressure with new tires

[wright97]

So, this may be a dumb question, but i can't find the answer anywhere. I have a 2019 2500 limited. I am looking to put a leveling kit on it and swap tires/wheels. However, i am not sure how to address the tire pressure sensors. I assume the new tires will have a much lower pressure. Right now i get a warning if the pressure drops below 60 PSI. I don't see anywhere to adjust that and i don't want a constant warning for low tire pressure with new tires.


Thanks in advance.

 

[LateToTheParty]

You'll need something like AlfaOBD or the AEV ProCal Snap to change those settings.

 

[skidoorulz]

I assume you have a 2500 or 3500 HD. Any tire that you will buy that is rated for that truck is going to be 80PSI max but should never run less than 65 PSI in my opinion. Unless you are getting 30 inch wheels with rubber bands for tires then I suggest you get a Subaru.

 

[wright97]

Yes, 2500 HD. Okay thanks. I haven't looked at the PSI ratings, was just assuming that they'd be lower than 65 PSI. This is my first Dodge and my first HD. Thanks

 

[H3LZSN1P3R]

I assume you have a 2500 or 3500 HD. Any tire that you will buy that is rated for that truck is going to be 80PSI max but should never run less than 65 PSI in my opinion. Unless you are getting 30 inch wheels with rubber bands for tires then I suggest you get a Subaru.

A Bigger tire requires less psi its about making a good contact patch on the ground....

 

[H3LZSN1P3R]

So, this may be a dumb question, but i can't find the answer anywhere. I have a 2019 2500 limited. I am looking to put a leveling kit on it and swap tires/wheels. However, i am not sure how to address the tire pressure sensors. I assume the new tires will have a much lower pressure. Right now i get a warning if the pressure drops below 60 PSI. I don't see anywhere to adjust that and i don't want a constant warning for low tire pressure with new tires.


Thanks in advance.

In my 19 2500 My 8.4 infotainment center has the tpms adjustment

 

[skidoorulz]

A Bigger tire requires less psi its about making a good contact patch on the ground....

In my opinion tire pressure is all about load carrying. You need to raise your tire pressure if you are hauling greater loads to stiffen the sidewalls and keep the contact patch equal on the ground no matter the size of the tire. If a tire is to low on pressure you could get a cupping in the center of the tire at the contact patch. To high of pressure will do the opposite. It will cause a high spot in the center. But I am no tire guy just thinking logic wise.

 

[H3LZSN1P3R]

In my opinion tire pressure is all about load carrying. You need to raise your tire pressure if you are hauling greater loads to stiffen the sidewalls and keep the contact patch equal on the ground no matter the size of the tire. If a tire is to low on pressure you could get a cupping in the center of the tire at the contact patch. To high of pressure will do the opposite. It will cause a high spot in the center. But I am no tire guy just thinking logic wise.

You are correct thats why you should always do the chalk test empty and when loaded with what ever you haul normally as most people haul very little weight.... by doing the chalk test you can find the proper inflation pressure that yields a good contact pattern.... also you wont get cupping from low or high pressures cupping is from alingment, balance, or shocks typically

And unless you have a 5th wheel or a massive bumper pull trailer the extra weight on the trucks tires is minimal

 

[jadmt]

I assume you have a 2500 or 3500 HD. Any tire that you will buy that is rated for that truck is going to be 80PSI max but should never run less than 65 PSI in my opinion. Unless you are getting 30 inch wheels with rubber bands for tires then I suggest you get a Subaru.

No need to run 65psi on a set of e rated 35 or 37's.

In my 19 2500 My 8.4 infotainment center has the tpms adjustment

that just alerts you when you reach a certain psi it will not lower the threshold.

 

[H3LZSN1P3R]

No need to run 65psi on a set of e rated 35 or 37's.

that just alerts you when you reach a certain psi it will not lower the threshold.

You dont need to run that much pressure if your unloaded that will just wear the tire centers out faster than the shoulders 35s should be around 55psi and 37s around 50 psi with a load on

 

[jadmt]

You dont need to run that much pressure if your unloaded that will just wear the tire centers out faster than the shoulders 35s should be around 55psi and 37s around 50 psi with a load on

I run 45 in back and 48 in front on my 35's.

 

[kobra]

I assume you have a 2500 or 3500 HD. Any tire that you will buy that is rated for that truck is going to be 80PSI max but should never run less than 65 PSI in my opinion. Unless you are getting 30 inch wheels with rubber bands for tires then I suggest you get a Subaru.

Actually, it's not as simple as that...

First, compare just 2 size of tires that I will fit on my 2020 3500 ltd:
1. the OEM LT285/60R20 tires, load range E, load index 125, carrying capacity of 3640lbs at 80psi
2. a replacement LT295/70R18, also load range E, but load index 129, carrying capacity of 4080lbs at 80psi
On the tire in example #2 above, you can reduce air pressure by about 10psi all the way around and maintain the same MAX load capacity. So, I can run 70psi rear and 55psi front, even if I am fully maxed out on my weights, and have the same tire carrying capacity.

Second, tire pressures as you've described are for vehicles that will be loaded to near max capacity. Have a look at the following tire pressure chart for the OEM tire size:
https://tirepressure.com/lt285-60r20-tire-pressure
To show what that means for my 3500 ltd when empty, the rear axle empty weight is less than 3500 lbs total. Using the above chart, on the OEM tires, I could air down to 40psi and still have several hundred pounds of extra carrying capacity. For the front tires, where my empty axle weight might be ~5000lbs, I could run at 50psi and still be more than adequate.
BTW, I've tried that low and the OEM tires get too squirmy on the road, so empty I settled on about 55psi as a good compromise.

On an HD truck where empty and loaded weights can vary by thousands of pounds, adjusting air pressure will help with tire life and ride quality. As others have mentioned, a chalk test can help. (It's winter here so I can't do the chalk test)

IMHO, No need to run the full pressures of 80/65psi when empty. Look on tirepressure.com or other sites to help you make the decision on the optimal tire pressure for the load you are hauling (or lack of load).

B

 

[DMC1]

I currently run 55psi in my 35's. I chalk test my tires without load on the truck and with load on the truck. I check my pressure regular especially with temperature swings and adjust accordingly.

I also have an AEV Snap to adjust TPMS if needed.

 

[lovegolf44]

Actually, it's not as simple as that...

First, compare just 2 size of tires that I will fit on my 2020 3500 ltd:
1. the OEM LT285/60R20 tires, load range E, load index 125, carrying capacity of 3640lbs at 80psi
2. a replacement LT295/70R18, also load range E, but load index 129, carrying capacity of 4080lbs at 80psi
On the tire in example #2 above, you can reduce air pressure by about 10psi all the way around and maintain the same MAX load capacity. So, I can run 70psi rear and 55psi front, even if I am fully maxed out on my weights, and have the same tire carrying capacity.

Second, tire pressures as you've described are for vehicles that will be loaded to near max capacity. Have a look at the following tire pressure chart for the OEM tire size:
https://tirepressure.com/lt285-60r20-tire-pressure
To show what that means for my 3500 ltd when empty, the rear axle empty weight is less than 3500 lbs total. Using the above chart, on the OEM tires, I could air down to 40psi and still have several hundred pounds of extra carrying capacity. For the front tires, where my empty axle weight might be ~5000lbs, I could run at 50psi and still be more than adequate.
BTW, I've tried that low and the OEM tires get too squirmy on the road, so empty I settled on about 55psi as a good compromise.

On an HD truck where empty and loaded weights can vary by thousands of pounds, adjusting air pressure will help with tire life and ride quality. As others have mentioned, a chalk test can help. (It's winter here so I can't do the chalk test)

IMHO, No need to run the full pressures of 80/65psi when empty. Look on tirepressure.com or other sites to help you make the decision on the optimal tire pressure for the load you are hauling (or lack of load).

B

So taking the max load for both the front and rear tires at their respective max PSI (65/80), this means a combined cargo capacity of 6170lbs-front and 7280lbs-rear? Of course I'm not taking into account the GAWR which shouldn't be exceeded but the total tire cargo capacity exceeds that of the truck GVWR which would make sense. Am I on track or missing something important?

 

[Chris.Gio]

Ram ”requires” 65 psi. Not agreeing or disagreeing, just stating what my door jam says. Based on this, I think running 65 is fine. The tires allow up to 80 but the tires also think my GVWR is over 10k.

im running 70 front and 65 rear for now. Truck 2 days old so subject to change!

 

[kobra]

So taking the max load for both the front and rear tires at their respective max PSI (65/80), this means a combined cargo capacity of 6170lbs-front and 7280lbs-rear? Of course I'm not taking into account the GAWR which shouldn't be exceeded but the total tire cargo capacity exceeds that of the truck GVWR which would make sense. Am I on track or missing something important?

I agree - and yes it is normal for the tire capacity to exceed the GAWR...

B

 

[kobra]

Ram ”requires” 65 psi. Not agreeing or disagreeing, just stating what my door jam says. Based on this, I think running 65 is fine. The tires allow up to 80 but the tires also think my GVWR is over 10k.

im running 70 front and 65 rear for now. Truck 2 days old so subject to change!

Yes, manufacturers choose the pressure and that is the "legal" recommended pressure from the factory. Since 2008, manufacturers no include a "supplemental tire pressure guide" (or similar) with the owners manual. Before that, many truck manufacturers included the tire pressure chart and one could adjust the pressure according to the load (especially empty vs loaded).

Manufacturer legalities aside, all tire manufacturers still publish tire pressure charts, and an owner is free to choose the tire pressure that best matches the load. When you consider a 3500 SRW truck, empty vs loaded, the front axle may vary by about 1000lbs or so. But the rear axle may vary by 3000lbs!
In practical terms, for the front tires, I think there is a bit that can be gained by lowering and raising those tire pressures; but relatively speaking they vary less, so 65psi could be very ideal empty or loaded on the front. IOW, might not be worth the bother to change.

But for the rear tires of your 3500 SRW, I would highly recommend using a tire pressure chart for your tires to safely lower the tire pressure when empty. Even if you wanted to lower the pressure in the rear to match the 65psi of the front, you will notice a much softer ride. But considering your front axle empty is about 5000lbs and your rear is only 3000lbs, you can make the case that the rear tires should have the pressure lowered below the fronts. Again, I find that even though a tire pressure chart could recommend 35-40psi, I keep the rears at 55psi or they start to feel too squirmy.

hth

B