Determining Tire Pressure
I have read that you should not pay much attention to the inflation psi marked on the tires, but rather go by the vehicle recommendation printed on the door edge. In other information I have found ch...
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This a quick math method for tire air pressure. It can serve as a baseline and on the low end due to axle weight and not tire inflation target(s). I would then put three or four or five chalk marks across the tread of each tire and drive the straight line for a bit. The amount of chalk left on the tire or not helps determine best pressure(s) for your vehicle. I release all liability from myself and have put on the flame suit.
My background with this quick method stems from a more complicated approach to tire pressure from driving the VW Bus and Vanagon for a decade and a half.
I will use the data from our 73 Dodge B30 Kodiak 20'r.
Front max capacity is 3300# Rear max capacity is 5700# Max GVXR as mfg is 8300#
Front - 3300 equates to 1650 per wheel
Rear - 5700 equates to 2850 per pair that equates to 1425 per wheel
Tire is a Load E , 2680 # at 80 psi for single and 2405 for duals at 80 psi
Front - 1650/2680 x 80 equals 49 psi
Rear - 1425/2405 x 80 equals 47 psi.
easy peasy, right?
My two numbers would be a baseline for (that) tire to support the intended weight based on Max GVWR.
If I used a Load D tire with 65 max psi the numbers would be higher for the same vehicle.
One of the keys is to figure baseline tire pressure for the tire you have installed on the vehicle. My numbers may sound low but that's because the tires have a large capacity. The owners manual has tire inflation tables but I find it hard to understand. Plus the table is based on bias ply tires. But, when I narrow down the few numbers I can understand, My quick math come out within five psi so I'm all good.
I'm still gonna do the chalk test but will wait until I put a few miles on the new tires to break them in a bit.
Hope this helps. I welcome more education and replies. YMMV
My background with this quick method stems from a more complicated approach to tire pressure from driving the VW Bus and Vanagon for a decade and a half.
I will use the data from our 73 Dodge B30 Kodiak 20'r.
Front max capacity is 3300# Rear max capacity is 5700# Max GVXR as mfg is 8300#
Front - 3300 equates to 1650 per wheel
Rear - 5700 equates to 2850 per pair that equates to 1425 per wheel
Tire is a Load E , 2680 # at 80 psi for single and 2405 for duals at 80 psi
Front - 1650/2680 x 80 equals 49 psi
Rear - 1425/2405 x 80 equals 47 psi.
easy peasy, right?
My two numbers would be a baseline for (that) tire to support the intended weight based on Max GVWR.
If I used a Load D tire with 65 max psi the numbers would be higher for the same vehicle.
One of the keys is to figure baseline tire pressure for the tire you have installed on the vehicle. My numbers may sound low but that's because the tires have a large capacity. The owners manual has tire inflation tables but I find it hard to understand. Plus the table is based on bias ply tires. But, when I narrow down the few numbers I can understand, My quick math come out within five psi so I'm all good.
I'm still gonna do the chalk test but will wait until I put a few miles on the new tires to break them in a bit.
Hope this helps. I welcome more education and replies. YMMV
