Tire Air Pressure

I’ve put the same make and size stock tires on my '05 Cavalier that it came with, but the tire pressure on the tires recommends 51 psi max & the inside sticker on the door says to inflate to 30 psi. Which is correct? Follow the tire or the sticker inside the door? 21 psi is a big difference.

Follow the sticker, the tire # is a do-not-exceed number.

If your doctor told you that he did not want your blood pressure to exceed…let’s say…140/90, that does not mean that he thinks that 140/90 is a desirable blood pressure, and in fact, this is a value that he does not want you to exceed. As texases stated, “51 psi max” is the maximum safe inflation pressure for this tire.

The correct pressure for your vehicle is on the sticker on the door jamb.

The 51 PSI is an absolute maximum safe pressure rating for the tire, the absolute top limit. The 30 psi is the correct pressure for your car.

The door sticker, 30 psi, is the pressure you should use.

Max pressure is just that, the maximum allowed for the tire. The max pressure is not the pressure for everyday use.

And your OLD tires probably said around 51 psi Max also.

Use the sticker on the door. Putting 51 psi on that car…the first speed bump you hit the car will probably fly 10’ into the air.

There is a difference between maximum pressure and recommended pressure. The tire has one. The label on your car has the other.

"the tire pressure on the tires recommends 51 psi max & the inside sticker on the door says to inflate to 30 psi. "

Exactly  It recommends a Maximum of 51 psi.  In other words if the sticker on your car, says 30 then the tyres have 51 on them, they are OK for your car, but if they had 25 on the tyre, then it would not be safe on your car.  

The worm maximum is key.  It does not mean that 51 psi is recommended for your car or any specific car.

You never said what tires it came with. Some tires are also for light trucks and would have a high maximum pressure if the truck was at maximum weight. We want the numbers that look like P225/75R16. Those could go on a truck.