Tire Air Pressure

[LouisanaJeeper]

Originally posted by Lost Pup

I would be concerned offering this as many tires are changed from factory recs and the pressure on the sill might not be the best suggested tire pressure.



I tend to read from the tire for max air pressure #.

This practice is totally wrong. You want to go off the suggested pressure on the door panel. If you change the size of your wheel/tires, generally you add more pressure if you are going to a smaller air volume tire and reduce pressure if you are going to a larger volume tire. Unusually this within 10psi of the factory spec unless you are making drastic tire size changes. The psi listed on the sidewall is usually max. psi and is usually 15-20psi more than the ideal pressure on most cars.

The chalk method listed above is the best procedure if you are unsure about non-stock tires.

[Myles]

36-40 psi is not over inflating. Bridgestone and Dunlop have told me that they consider over inflation at 50+.



I use 36 to increase sidewall stiffness and braking performance. A performance driving school told me that they think that 36 is the best trade off between performance and comfort. Manufacturers reconmendations are the best pressures for comfort.



On track days i go up to 42 psi.

[Brad B]

To get the optimum pressure for the conditions you drive in requires a quality needle pyrometer. (not digital, they are not as accurate)



When the tire is hot you measure the heat across three spots in the tread of the tire. (Outside, middle, inside) You want the temperatures to be equal throughout the width of the tread.



If the temps are hotter in the middle you are overinflated. If they are hot at the edges you are underinflated. If the temps are dramatically different on one side compared to the other then you have to consider alignment issues.



Longacre is one of the leading brands. They range in price from $100 to $500.



We use them at the track to determine proper pressures and chassis set up.

[5918mike]

sheep, are those tires on your IS300 aftermarket, cause my stock 17`s are nowhere near 50psi, i believe the recommended is in the 32 psi range.



I have a compressor in my garage and it`s a weekly routine to check the pressure. I know alot of people who have never checked their tires.

[kevmo327]

I run both my jeeps at 34-36 PSI for everyday driving.....Just last week one of the girls in my office was compaking that her car felt funny and when i looked her rr tore was almost flat (5 lbs of air)...when i asked her if she ever checked her tires she looked confused