I have a 07 F150 with 235/70/17 tires.Gonna put 235/65/18 tires on factory FX-4 wheels. What would be a good tire pressure to run?

 

Well considering you'll have the tpmsensors just use what the factory specs are.

 

Check the sticker on the drivers door pillar. It will probably say 35lbs, you may want to bump that to 38 or so.

 

I would go with the rated or recommended pressure from the tire manufacturer. They would probably know the best setting to make the tires last and ride the best.

 

oh shoot - I think mine are at 40...need to check now!

 

The tire is marked with a MAXIMUM pressure by the mfg; if you use this (often 55 lbs or so) and are not carrying a heavy load you'll shorten tread life and excessively wear the center area of the tread. Hurts traction and ride as well.

That's why the vehicle recommendation on the door pillar is your best guide.

 

Every tire has a different max. That isn't what you go by. Go by the tire plac card. At the most I would go is 40 psi.

 

You are correct about the max rating stamped on the tire yes.I was thinking more along the lines of contacting the manufacturer and getting an ideal psi that would give you the best wear, ride and mileage. I don't know if the rating on the door of my truck would apply to my tires as they are aftermarket. I'm not sure what was stock because I bought it with them already on it. I know you are correct about not putting max pressure in 'em though because I had a set wear in the middle one time from too much pressure.

 

It still applies to your truck

 

Thanks for the info. I had my truck at the dealer today and they made sure the psi was correct.