5th Wheel Trailer Tires

Mike G · May 5, 2011

So we just picked up a new-to-us 5th wheel and the tires need some air added. I was looking at the tire and they are 235/16 goodyears, which indicate a max air pressure of 80 psi cold. The trailer is a 32ft 8k lbs unit. I am used to putting 40 lbs of air in my regular tires, do these need to be aired up that far (80 lbs) or is that a max guide. I don't think I ever put more than 50 lbs in anything I've owned....

--Mike

JDWLT · May 5, 2011

Mike,

I have a 32' Mobile Suite 5th wheel. I always keep the max tire pressure that is on the side wall of the tire. In my case it is 110PSI COLD. You probably have a 16" E rated tire and they run 80 PSI COLD. If you don't run them at 80 you over heat the tire and will blow one out. Also check the date that the tire was manufactured. DOT (XXXX). That is (1130) would be 2011, 30th week of the year. If the tires are more than 5-6 years old I would change them even if they have alot of tread left. If the side walls show cracking, change them.

Enjoy your new 5th wheel but tires are very important on a trailer.

Walt

Matt_ · May 5, 2011

You want to take max weight rating of the trailer and divide that by the number of tires (even though some load will be taken up by the truck). Then you look up your size tires on the TRA (North American Tire & Rim Association) Inflation tables to find the appropriate pressure. Take notice that the same sized tire has different ratings based on if its run as a single or dual, so that is a factor.

Here's a link that will help you determine the correct pressure:

http://marktg.toyotires.com/file/loadinflationtable.pdf

06_GMC · May 6, 2011

I would just Run the max that your sidewall says for COLD. I agree with everything Walt said above.

Mike G · May 6, 2011

All good stuff, many thanks guys.

I actually replaced all my boat trailer tires last year just because I had one blow at the end of the previous year and figured the rest would be close behind...