Tire Pressure Recommendations

[Ray,IN]

I used to tow a 15,500# 5er with an 02 Duramax dually. I ran 80 psi in front tires and 65 psi each in rear dual tires. This was the best tire pressure setup I found, all 6 tires wore evenly across tread surface and rig handling was steady and sure.
That must have been a good decision because i got over 60,000 miles each from 2 sets of B.F. Goodrich 16" tires on that truck towing a 5er all over the U.S.A., including a trip to Alaska.
FWIW, I never did have even one tire problem on that truck.


You can get a visual of tire wear by making a wide mark/band across the tread of each tire with chalk, and observing where the chalk wears off.

[balvert]

I have scaled my 2021 Ram diesel dually both unloaded and with the fiver on. Using the load inflation tables, I run 65 front and 35 rear unloaded. I get a decent ride. Loaded with my heavy fifth wheel, I run 70 up front and 65 rear which are the numbers on the door frame.

[drfife]

I do not rotate the tires on my dually. The cost of multiple rotations is greater than the cost of a set of tires. The fronts on my 3500HD require replacement every 50K miles. Rears about 70K miles.

[Texas Sooner]

Originally Posted by wandering1

SOwhy dont you call Michelin and find out, dont rely on all the tire expert wannabes.

I received an email from Michelin that said that they cannot provide Load and Pressure recommendations for towing purposes - go by the pressure on the side of the tire.

[wolfe10]

Originally Posted by Texas Sooner

I received an email from Michelin that said that they cannot provide Load and Pressure recommendations for towing purposes - go by the pressure on the side of the tire.

Can you say LAWYER SPEAK!


Towing/not towing, the load on the tires/axles IS what determines the correct minimum PSI. Any other answer ignores physics.

[Texas Sooner]

I just stopped by a CAT scale with full fuel in the truck and got the following weights:

Steer Axle - 5120 lbs
Drive Axle - 3900 lbs

So, using these axle weights along with the Load and Pressure recommendations, I should run 65 PSI in the front tires and only 35 PSI in each of the four rear tires? If I had only two rear tires I would run them at 45 PSI?

I know that when I pull a trailer, the rear tires will have to be adjusted to account for those numbers which I will have in a few days. I just want to make sure that I'm figuring this out correctly.

[jadatis]

Answer to post #34

If you also give tire specifications, I can calculate a highest pressure , at wich comfort and gripp is still acceptable.
This then gives maximum reserve.

[balvert]

Originally Posted by Texas Sooner

I just stopped by a CAT scale with full fuel in the truck and got the following weights:

Steer Axle - 5120 lbs
Drive Axle - 3900 lbs

So, using these axle weights along with the Load and Pressure recommendations, I should run 65 PSI in the front tires and only 35 PSI in each of the four rear tires? If I had only two rear tires I would run them at 45 PSI?

I know that when I pull a trailer, the rear tires will have to be adjusted to account for those numbers which I will have in a few days. I just want to make sure that I'm figuring this out correctly.

Correct. Those are my calculations as well. Makes for good ride unloaded and even wear across the duals. I did the chalk test to confirm it.

[Scooter363y]

I had a similar problem with my rig a diesel pusher. I got new tires (Michelin’s) and wanted to start off on the right foot. So after installing the tires I had it weighed just as it was going down the road.. I came up with a 10k and 20k weights for front and back loads on the axel’s.

The pressure/weight charts from Michelin says a pressure of 95-100 psi for each tire. But the sticker inside the coach says 100psi rear and 115psi in the front. Very confusing! So I started with 100psi all around. The rig rides but responsiveness was kinda sluggish. Every year I increased the front pressure by 5 until I got to 115. I would say that the handling is sportcar like but it got better.

Morel of this story get weighed and pick a starting point and try it. If you don’t like it change it till you get something you do like! Plan, do, check, action.

RV safe
Scooter

[fast_st]

Originally Posted by Texas Sooner

I just stopped by a CAT scale with full fuel in the truck and got the following weights:

Steer Axle - 5120 lbs
Drive Axle - 3900 lbs

So there are a couple goals, good ride with a impact absorbing tire, good contact patch and most importantly avoiding excess flex/heat that makes all those road gators you see out there from heat failure.



An inexpensive non-contact IR thermometer is a great tool while towing, you can compare tire temperatures and they'll even show left/right bias if you have more load on one side. Go by the tables and run it down the road, then measure. Unscientifically I figured 20-25 degrees over ambient was a good range for me and when badly overloaded it would need a pressure above sidewall ratings. All of the published tire pressures assume worst case of max loading and max sustained speed (rated) Speed rating on light truck tires is typically either 112 or 118 mph, lower speed means lower heat.

[ArtJoyce]

Originally Posted by Scooter363y

I had a similar problem with my rig a diesel pusher. I got new tires (Michelin’s) and wanted to start off on the right foot. So after installing the tires I had it weighed just as it was going down the road.. I came up with a 10k and 20k weights for front and back loads on the axel’s.

The pressure/weight charts from Michelin says a pressure of 95-100 psi for each tire. But the sticker inside the coach says 100psi rear and 115psi in the front. Very confusing! So I started with 100psi all around. The rig rides but responsiveness was kinda sluggish. Every year I increased the front pressure by 5 until I got to 115. I would say that the handling is sportcar like but it got better.

Morel of this story get weighed and pick a starting point and try it. If you don’t like it change it till you get something you do like! Plan, do, check, action.

RV safe
Scooter

I did the same. used the load psi chart added 10 psi, added more psi several times and handling improved. But the ride began to become more harsh. I backed off the PSI to where im at the chart plus 15 psi. Slight loss in the handling but much better ride.

[Texas Sooner]

Originally Posted by jadatis

Answer to post #34

If you also give tire specifications, I can calculate a highest pressure , at wich comfort and gripp is still acceptable.
This then gives maximum reserve.

Michelin Primacy XC tires - all six are LT235/80R17 120/117R TPC BSW

[Texas Sooner]

Originally Posted by ArtJoyce

here is a chart https://tirepressure.com/lt235-80r17-tire-pressure

This is a very informative website - thanks for sharing!

[Kid Gloves]

Originally Posted by Texas Sooner

I received an email from Michelin that said that they cannot provide Load and Pressure recommendations for towing purposes - go by the pressure on the side of the tire.

So, they told you they can’t provide a pressure recommendation, and then they provided one. Sort of.

That’s comforting.