Tire pressure (I feel silly for asking)

As some you know I made a recent post about my gas mileage, so I started with some basic crap like making sure my tires were fully inflated which led me to my confusion, I could not see on the tire where the PSI was so I looked my tire up (BFgoodrich A/T 275/55/20) and it says max PSI 65 @2680LB. Usually I found PSI to be between 33-40, but I inflated them to 60PSI and the ride feels a lot more firm and steering is really easy, but I am still left with the feeling that this is not the best PSI.

 

Over inflating the tires will make them wear out quicker. Might get better mileage at the cost of a new set of tires in half the time. Also you risk losing traction in rain.

 

I run mine at 32. I’d rather sacrifice 1-2mpg for the comfort than ride around on rocks

 

Girlfriend said it was 65 but I had to make sure.

Yeah I am afraid of uneven wear (all in the center), ill most likely put them back to 40 and start by changing the plugs to see if i can improve upon my 7.5MPG

 

There is a thread here about purging out the gas system, changing filters and what not that got a lot better mileage. Search it out.

 

I run 40 psi on my Toyo AT2

 

Same here

 

65psi max means you probably have load range D tires. In order to maintain your load capacity on a 275 55r20D, you need to run 55psi or more. Anything less does not maintain the OEM load capacity

 

I called BFGoodrich and took their recommendation for my KO2's.

 

Max inflation on the side wall is for load rating. Mine are load range E, so 80 psi. But at that pressure without towing or a bunch of stuff in the bed they ride like crap. I find 35 to be just right. 20 offroad, 35 normal driving and 60-80 for loads is what works for me. Chalk test with normal load will tell the tale.

 

I have the same load range D AT KO2 tires. The manufacturers suggested pressure is on the driver's door sticker. My particular truck says 49 PSI. The pressure on the sidewall is the max cold pressure and for load range D should be 65. IMO you don't want to run either constantly. The 65 PSI is to run fully loaded. For normal everyday driving I take the max tire pressure and the sticker pressure and start somewhere in between. Take a piece of chalk and color across the tread of a front tire and a back tire. Roll forward about 50 feet and check your marks. What you want is for the line to be rubbed off all the way across, if only rubbed off on the sides add air, If only rubbed off in the center decrease air. Do this until it's worn evenly. You'll want to do this while tires are cold and vehicle hasn't been driven over a mile or so. Always check and adjust tire pressure when cold.