285/70/17 BFG AT. What the best psi?
#11
06-25-2009, 12:26 PM
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I found this formula a while back when I was trying to determine the same thing. FYI, if you change tires from the manufactures original/spec'd tires you best pressure will probably change.
Tire Pressure = Axle Weight ÷ # of Tires ÷ Tire Weight Rating X Maximum Tire Pressure (of new tires)
For my 2006 1500 I hve the following:
Front - Axle Load Weight = 3700
# of Tire = 2
Tire Rating = 3640
Max Pressure = 80
Rear - Axle Load Weight = 3900
# of Tires = 2
Tire Rating = 3640
Max Pressure = 80
This calculates out to: about 41 psi for the front and 43 psi for the rear. This would be the max loaded weight. I have backed down about 5 to 7 psi from that for an acceptable ride and performance level.
Hope this helps.
Tire Pressure = Axle Weight ÷ # of Tires ÷ Tire Weight Rating X Maximum Tire Pressure (of new tires)
For my 2006 1500 I hve the following:
Front - Axle Load Weight = 3700
# of Tire = 2
Tire Rating = 3640
Max Pressure = 80
Rear - Axle Load Weight = 3900
# of Tires = 2
Tire Rating = 3640
Max Pressure = 80
This calculates out to: about 41 psi for the front and 43 psi for the rear. This would be the max loaded weight. I have backed down about 5 to 7 psi from that for an acceptable ride and performance level.
Hope this helps.
#12
06-25-2009, 01:06 PM
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#13
06-26-2009, 01:09 AM
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I run my 265/70-17 bfg's at 35psi and have for the last 6K miles since I got them. I just took it in 2 weeks ago to the dealer for my free oil change and borrowed their tire tread wear gauge, I have even tread wear across the tire and all four tires are pretty much identical. MAX tire pressure is only for heavy loads and they only print that on the side of the tire for liability purposes. I have a good friend who's exceeded the max PSI on his front tires by 20psi for short times without a ever a problem.
#14
06-26-2009, 07:01 AM
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wheeler, i'm in Ontario and run my bfg's at 40 psi all year round. If your worried about tread wear, run a chalk line from side to side across your tread, take it for spin around the block. If it wears evenly then your good to go for your pressure, if not adjust up or down accordingly. Really easy check for piece of mind.
Oh yah, GREAT forum here all, it's helped me out of a few binds. Thx to all
)
Oh yah, GREAT forum here all, it's helped me out of a few binds. Thx to all
)
Last edited by selsyn; 06-26-2009 at 07:03 AM.