Tires

I just bought new tires for my 2003 chevy express van. I need to know if I inflate the tires to the chevy specs 55psi front 80 psi rear or do I inflate to what it says on the new tires? can anyone help.

The “Maximum Pressure” that is imprinted into the tire sidewall is just that–the maximum. Think of it like blood pressure. If your doctor told you that your blood pressure should be no higher than XXX, that does not mean that XXX is a desirable blood pressure, and in fact, it is a value that you should be careful not to exceed.

That particular tire will fit a variety of vehicles, with varying weight distributions, varying handling characteristics, and varying cargo capacities. And, the proper inflation pressure for those same tires will vary from one vehicle to another–but no matter what vehicle they are mounted on, the pressure should never exceed the numbers that you see on the sidewall.

Since GM has designated wildly different pressures for the front and the rear tires, that tells you that their testing has yielded some important information about the relative pressure bias front to rear. If you don’t follow their recommendations, you will likely wind up with handling that is unpredictable and dangerous, due to overinflation.

Follow the vehicle manufacturer’s guidelines, and if you want to add a couple of extra lbs. of pressure in the interest of fuel economy, feel free to do so, as long as you preserve the relative pressure bias between the front and the rear tires. In other words, if you add 2 lbs. to the front tires, also add 2 lbs. to the rear tires.

On every vehicle sold in the US, there is a sticker ? commonly called the vehicle placard - that lists the original tire size and the proper pressure for that size. The placard is usually located on a doorpost or in the glove box ? but sometimes it is located in the trunk or on the fuel filler door.

If you are using the same size as listed on the placard, then the placard pressure is appropriate. (BTW be careful about the letters in front of or behind the tire size. They are important. There is a difference between a “P” tire and an “LT” tire - and your vehicle requires the use of an “LT” tire. if you got “P” tires by mistake, IMMEDIATELT take them off. They are going to fail - not enough load carrying capacity!)

I second that statement. The high pressures that you state, 55 psi and 80 psi, are typical for ‘LT’ light truck tires. If the maximum pressure on the new tires are only 45 or 50 psi, they put the wrong tires on, most likely ‘P’ for passenger vehicle, and you are risking SERIOUS injury. ‘P’ tires do not have the load bearing ability the van requires, and WILL BLOW OUT! Take it back immediately and get the right tires put on.

That is an excellent point. I was thinking in terms of the usual posts that confuse the vehicle placard’s advice and the information on the tire sidewall. If the OP does indeed have the incorrect “P” type tires mounted on his truck, using the vehicle manufacturer’s inflation ratings would cause those inappropriate and unsafe tires to be grossly overinflated. And, as was stated, the “P” type tires simply do not have the load-bearing capacity that the van needs in order to be operated safely.

OP–This is really important! Check those tires immediately! If the tire size includes the letter “P”, rather than the correct LT designation, you need to get them replaced immediately. If they are the correct LT-designated tires, then simply follow GM’s inflation directives.

re read the previous two responses. it does sound as if you got the incorrect tires put on the van.

this is one of the problems with going to a ‘discount’ tire place… sometimes you get the discounted advice too!

to meet your vans load carrying ability you need to have tires which are rated for the particular weight your van is capable of carrying. often many vehicles have tires on which exceed the capacity of the car, so you never have to worry about ‘blowing up’ the tires. BUT, in this case, you should be inflating to the pressure stated on the name plate on the door. if the requirements are to inflate over what the tires say is the max pressure… stop now!

if the tires can’t take that much pressure, buy new!

Your owner’s manual and the sticker on the van list the recommended pressure. The tires list the maximum pressure. I don’t understand why people get these concepts confused.