which do we follow on tire inflating psi the tire recommended on the tiresitself or the the sticker on car?

Answer 1

Tires tend to have the MAXIMUM safe pressure listed on the sidewall; the sticker on the car is the car manufacturer's recommended pressure for that vehicle (since the tires may be used on more than one vehicle with different weight, speed and handling characteristics).

That being said, it's ALWAYS safer to be a couple of PSI higher than the recommended setting rather than lower, for several reasons. First, higher pressure reduces rolling resistance, which contributes to better fuel economy. Second, higher pressures (by just a couple of PSI at any rate) reduce overall wear on the tire by preventing it from rolling onto the sidewalls under hard cornering loads.

And third, the relationship between tire pressure and grip works like this. Competition drivers learn fairly early on that there is a "sweet spot" for tire pressure, at which that tire on that car will have the maximum traction at all times -- cornering, accelerating and braking. (It's fairly easy to find this sweet spot; if you're interested, write me or ask another question.)

So let's say that you've determined that the sweet spot for your tire is 37 psi. Being higher or lower than this figure reduces the overall grip -- but being LOWER reduces grip more, for the same number of PSI, than being higher does.

This means that if 37 is perfect, 40 is safer than 33, even though they're both 3 psi off of the "perfect" value. (Mainly because a higher-pressure tire will be less likely to roll over onto the sidewall when you're cornering hard, as in competition.)

So the real answer is to keep your pressures at LEAST where the vehicle manufacturer recommended them, NOT lower, and don't exceed the maximum pressure printed on the tires.

Answer 2

The pressure number on the sidewall of the tire is the MAXIMUM allowable pressure for that tire (The Do Not Exceed limit.) The proper tire inflation pressures for the vehicle are posted on the driver's side door of the car, or on the door frame.

Inflating your tires to the maximum allowable pressure will cause a hard ride, poor handling and rapid wear of the rubber at the center of the tire. You should always use the vehicle manufacturer's recommendations for proper inflation, for the best ride and safest handling.

Answer 3

You should ALWAYS follow the vehicle manufacturer's instructions.

The pressure stamped on the sidewall is the maximum safe inflation pressure for the tire itself. Inflating the tires to a pressure different from the vehicle manufacturer's specifications will affect the handling characteristics of the vehicle, sometimes dangerously so.

Answer 4

Subtract 4 psi from the tire in the summer and 2 in the winter. If you're worried about gas milage, check into tire barn. they now use (I'm gonna misspell this) nitrogen. it suppose to increase milage by 2 mile per gallon, its super cheap too. like 3.00 for all for tires.


***BUT****

to answer your original question, always follow the tire, not the sticker. if the car came with an S rated tire and someone put Z rated tires on them, you could wind up putting 20lbs pressure to much if you follow the sticker.

Answer 5

Follow the instructions on the tire itself, because the car instructions tell the recommended pressure for tires that they put on the vehicle at the factory.

Answer 6

THE CAR
tyre pressure on tyre is usually maximum
so car variations overide ---except maximums
having said that manufacturers work together and car should have specific tyres fitted for safety reasons and vehicle ride quality
therefore if correct tyres are fitted as said by car maker tyre pressure should almost be the same in both cases
also you wouldn't get insurance if you change tyre size or rating
p.s. we say tyre in australia not tire-

Answer 7

The car. The manufacturer has determined how much pressure should be in the tire for max. handling and ride.

Answer 8

The depends on your preference as follows:

The higher pressure recomended on the tire will increase fuel economy, handling and longer tread life.

The manufacturers lower recomendation provides a smoother ride and modestly better traction under certain conditions.

It is your choice. I have always opted for the tire manufacturers recomendation.

Answer 9

I would use the tire. Whats on the car is just a recommendation in general as they don't know exactly what tire your using once you drive it off the lot.

Answer 10

Use the one on the tire. It's not always the same tire that was originally on the car.