Tire pressure question

My 13 inch PUP calls for 35 psi because it only weighs 2800 lbs. The manufacturer of my TT recommends 50 psi for the C rated ST tires.

My new D rated ST tires require 65 psi for their full rated load.

I would go with what the manufacturer of your unit recommends.

"I figured I would inflate them to 70 even though it said 80 on the sidewall"

You "figured" wrong. Inflate to manufacturer's recommended max pressure....unless you, as a tire engineer,....

Contact the manufacturer and see if you can get the inflation chart for the tire. This chart will tell you what weight can be supported by the tire at different PSI levels. If you're not running anywhere near the capacity of the tires then you can run lower pressures. However, 12" tires typically don't have that great of a capacity rating; around 900-1,500 lbs per tire. You may end up having to run them at 80 PSI just to support the weight on top of them.

wrenchbender wrote:
As a rule I inflate trailer tires to the max as stated on the sidewall

thanks,
I figured I would inflate them to 70 even though it said 80 on the sidewall

guy

As a rule I inflate trailer tires to the max as stated on the sidewall

NanciL wrote:
On a 12 inch tire if the sidewall has stamped "inflate to 80PSI -cold", do you go that high or lower ?

Jack L

You can inflate the tire to the tire stamped max air pressure of 80psi cold rating.

You should not go much higher other then gage accuracy unless the tire manufacture has granted special conditions that apply to that brand and type.

Can you go lower? you need to clarify the use of the tire and the type and you need to know the weight (loads) the tire is going to be subjected to. If this is an ST trailer tire used on a camper, or a trailer, the recommendation is to use the trailer manufactures pressure stated pressure. If they do not list one, on a trailer situation, use the max cold pressure as stamped on the tire.

If this tire is not an ST tire and on some other application, then using a load inflation table by that tire manufacture can tell you what PSI needs to be used for what weight rating.

You did not say what the application was of the tire or the tire type so it is hard to give a specific answer. With more info, we can help better on going lower pressure then max side wall cold pressure.

Hope this helps

John