Tire Pressure

[SLT556]

What tire pressure are you guys running? Sticker calls for 60psi in front and 80 in back. I think that's about max load pressure. I never have max payload, hence I'm think I don't need max pressure. I just lowered mine today to 55/70. I wouldn't mind dropping another 5 psi front and back. What does everyone else run? I'm seriously considering going to a 265 to run less pressure all around and get a smoother ride with a larger foot print on the pavement.

[cabletech]

I run 55 in front and 50 in the rear empty. I raise the rear to 75 when pulling our 5th wheel.

[crafty]

I'm running 55 psi all around and I will bump that up to 65 in the rear when I'm hauling a trailer. I've got 87,000 kms on the factory tires with 50% treadwear. They are rotated every 10,000 as well.

[DmaxMaverick]

Your sticker recommended tire pressure assumes you are loaded to capacity.

You could determine the ideal tire pressure by the actual weight at each wheel, and adjust the pressure according to the percentage of weight to capacity. OEM tires are rated at 3042# each, or a rear axle rating of 6084#. For example, if your rear axle is only carrying about 3000# (about 50% of capacity), then the ideal pressure is 40 PSI, or 50% of rated pressure. The same applies to the front, but I suggest increasing the pressure enough to account for dynamic loading. I use this method, and increase the pressure about 5-10 PSI to account for "unplanned loads" on the rear. It works to soften the ride as much as practicle, and wears the tread even.

My tires are 285/75/16D's, with a max load of 3305# @ 65 PSI, so my numbers are different. I generally run the front at 45 PSI, and the rear 30-35 PSI, unloaded, and increase the pressure according to my loaded weight. The ride is good and tire wear is even.

[RVC]

DM

Hope you don't mind me putting that in to an actual formula that I have used as a minimum allowable pressure.

Tire Air Pressure MINIMUM
axle weight / number of tires X max air pressure / weight rating of tires used = tire pressure needed
ex: 5000 lbs axle weight / 2 tires X 80 psi max air / 3042 rating of tire = 65.75 PSI needed.........
ex: 5000 lbs axle weight / 2 tires X 80 psi max air / 3415 rating of tire = 58.57 PSI needed.........

[hd90rider]

Well, I am towing 60% of the time and I run my tires at 65 frt & rear. Usually get 115k to 125k on the Firestones (this is my 3rd set) and rotate every 15k. :cool:

[SLT556]

Originally posted by RVC:
DM

Hope you don't mind me putting that in to an actual formula that I have used as a minimum allowable pressure.

Tire Air Pressure MINIMUM
axle weight / number of tires X max air pressure / weight rating of tires used = tire pressure needed
ex: 5000 lbs axle weight / 2 tires X 80 psi max air / 3042 rating of tire = 65.75 PSI needed.........
ex: 5000 lbs axle weight / 2 tires X 80 psi max air / 3415 rating of tire = 58.57 PSI needed......... Minimum for what?

[DmaxMaverick]

If a tire is carrying 'X' amount of weight, your tire pressure must be a minimum of 'Y' PSI. Less air pressure will cause an overload situation.

If you can do simple math, it is easy. Weigh your axle. Determine what percentage of the max rating is actually being used. Inflate your tires, using the same percentage of air pressure, compared to the max PSI. Add 10%, or so, air pressure to allow a safety margin.

Try searching previous posts in the various forums. It's been hashed out in length.

[BigO]

I work for a major tire company and they tell me HEAT is the worst enemy for a tire. In Phoenix, AZ I tried running mine at 55 in frt and 50 in rear. Loved the ride but it wore the tires faster and caused damage to the tires. When heat can not escape this causes the tire to break down. I now run mine up at 65 and 60 in the cooler months and push them to 70 in the summer. 100 + degrees in the air just imagine what the roads are at. When I drop my fith wheel in I push them up to 75. I will get around 55,000 miles out of my tires.

[Cracker65]

I run 65 in the front, all of the time, and I vary the rear from 50 to 65 depending on whether I'm light or loaded. The trailer puts right at 1,000 lbs on the ball and I use a very lightly stressed load equalizing hitch. This is with the original Goodyear tires. Per the load chart, I'm still "overkill" on the dualies - but Goodyear doesn't recommend anything less than 45 psi. The ride difference, when light, is like night and day between 50 psi and 65 psi on the duals! The front axle weight on the CC/LB dualie, with 4wd, sure doesn't leave much of a reserve capacity.

[Diesel Crat]

I run 60 all the way around. Going to push it to 65-70 for the summer pulling the 7K travel trailer. Gets better mileage and with current fuel price trends, well, lets not go there. smile.gif