tire pressures

[maintech]

I tow a 11500lb 5th wheel with my F350 dually, and had the tires inflated in Canada, while it was very cold. The rig handled fine, but lately here in Florida I felt the ride was harsh. When the pressures were checked they were found to be 70psi front and 60psi rear. The mechanic lowered them to the recommended pressure as per the door label, 60psi front and 40psi rear.

Should I raise them to tow or leave them as per the door label provided by Ford?

Is there a definitive authority I can check with?

thanks for any help available.

 

[IHC Power]

Those pressures don't sound correct to me but it's been a while since I looked in the door jam. I suggest for fuel economy running the tires at there rated pressure, basically the max on the actual tire without reference to Ford. I have found that they will wear better, last longer, and also increase fuel economy. The only downside is that the ride is less comfy, but hell were all driving 3/4 and 1 ton trucks so who cares anyway they ride like a caddy when loaded so...

 

[rammertide07]

My tires are rated 55psi but I run them at 50psi. Its helps to lessen the wear without killing the mpg. I have never heard of running 20psi difference between the rear/front...unless they are different tires. 40psi sounds too low to me.

 

[BIG JOE]

Best way ?

With your Load on-board or in tow.. Go to a CAT scale, get the front axle weight, and rear Axel weight.

Divide the front axle weight by 2.. rear axle weight by 4 (for DRW).. refer to the Tire Manufactures chart for Your specific tire..... for the recommended psi for each tire.. based on the front & rear math numbers.

Make any sense ?

I like to add 5 psi.. so I run 68 in the fronts.. 60 in the rears. Loaded or Un-loaded. Nice ride (for a 1 ton DRW).

Joe