Truck

[gride]

What should my tire pressure be on a 4x4 yukon with 285/55/20's. they are Michelin l/t that max psi @ 80. The gmc dealer took the liberty of dropping them to 35 when I had them @ 60.

[jbach]

not 60. read your door panel or if you want a mre accurate answer, google "tire chalk test"

[gride]

I've read the door panel, but its not for my tire/wheel size. Would 45 be acceptable?

[sodbuster88]

I've read the door panel, but its not for my tire/wheel size. Would 45 be acceptable?

This is a good read...might help.

http://nitrogentiremachine.com/prope..._inflation.htm

[AirTool]

What should my tire pressure be on a 4x4 yukon with 285/55/20's. they are Michelin l/t that max psi @ 80. The gmc dealer took the liberty of dropping them to 35 when I had them @ 60.

Gride- what you need to do is choose the air pressure based on the tire rating and weight on the tire. So,

1. It is preferred that you find the load chart for your specific tire on the mfg website. Most have them. If not, there is a generic chart based on Load Range examples: P metric "C" , LT "E" and so on.

2. Then, look on your door panel and get the axle weights front and rear. They are probably different. Then divide the axle weight by two and this is the load on the wheel.

3. Then go back to the chart and read what the pressure should be for that load.

If your dealer lowers the pressure of an LT tire down to 35, I would smack him. Most of those LT tires have a fairly high minimum pressure.

The LT and P I'm referring to is the designation before the tire size. Elsewhere on the tire the "Load Range" should also be shown. If not, get it from the website.

[gride]

i did a chalk test today and they seem just slightly under inflated. i'm going to put them to 40psi. should i put the rears up to 42 or so? i'm going riding tomorrow and will be trailering the boat.

[Zach@n3]

It's all reletive to the tire you are running and the weight of the vehicle. All of our 3/4 ton trucks called for 80 psi rear but that is simply to much tire pressure when not towing. The newer 3/4 ton ram's equipped with TPMS systems have whats called a light load setting. It allows you to run a lower rear pressure (40psi) without setting off the annoying low tire light. To much pressure wears the mid section of the tread. To little wears the outter edges of the tread.

On my (favorite truck I've owner) 99 R/T dakota I would run as little as 22-25 psi in the rears. The factory rating would eat up the center of the treads and kill tire life. Or maybe that was my driving habits .