Tire Pressure Question

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Aug 18, 2005 | 01:27 PM

KyEdExpedition

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Tire Pressure Question

I have a question about tire pressure: It says on the door of my Expedition to run 30 PSI in the front and 35 PSI in the back...however, we put off road type tires on the back a highway type tires on the front, so they are non-stock...on the front tires it says "MAX PSI 40" and the back says "MAX PSI 35"...so do I go by what it says on the tire or what it says on the door? Both sets of tires are the exact same size as stock.

-Kyle

Aug 18, 2005 | 02:25 PM

KyEdExpedition

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Bump!

Aug 18, 2005 | 03:25 PM

pitrow

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From: Cornelius, Oregon

Well, first of all, the pressure listed on the tire is the MAX pressure for hauling the max load the tire was designed for. If you're just doing normal driving, there is really no reason for you to be running the max pressure listed on the tire.

Personally I would start with the pressures listed on the door and adjust from there if the ride is too harsh or soft.

Aug 18, 2005 | 03:34 PM

MOOK929RR

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is your new tire the same size as your stock tire? The pressure listed on the inside of the door is for the stock size tire... If you are running a diff size, go off what it says on the tire. I have 285/70/17, and i think im running 40 all around.

Aug 18, 2005 | 06:58 PM

PaulC

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Go with the recommendations on the door. 1997-02 Expys are very sensitive to tire pressure. Too much air in the front tires will make your highway-driven Expy act like a cow trying to hoof across a frozen lake.

Aug 18, 2005 | 08:00 PM

mike02expe

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Listen to Pitrow... If you are running different tires than what was on your truck, then the door sticker means squat. You may be running the same size tire but a different load range. If you tire has a max tire pressure of 35, then try to run at 32 and adjust from there. If you are running a 8 or 10ply with a max of 75 psi, try running at 50 and go from there adjusting to the quality of the ride...If your tire size starts with a p, then it is a passenger tire. If it starts with LT, it means light truck and usually will carry a higher load range. example.. ply C= 6ply D=8ply and E=10ply... You would only want to run the max pressure if hauling a heavy load. Common sense...

Aug 18, 2005 | 09:38 PM

Luzer27

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From: Tucson

Dumb question but are all tires are the same size ? Your prifile lists a 4x4 and different sized tires in 4hi or AWD would be bad? Just checking. As far as pressure stay above 30psi to keep internal heat down then adjust for the ride you want. The off road tires will ride rough due to the thicker sidewall and mesntioned by mike. Also tire pressure will play a roll in how the tires wear. To much and the tire will bald in center to little and tire will show excess wear on outside of tread. Also with gas prices more pressure equals a little less at the pump. I would suggest setting them to 35 and drive for a week and by then you will forget about all about it and be used to the ride. Tire pressure is not that critical as long as it is not low and the front and rears are equal side to side, it just caught alot of attention through the problems Ford and Firestone had. Good luck.

Dave