2003 Chevy Impala tire pressure

djd1kimpala

Hello my car has 225/60R16 tires in the front that the recommended tire pressure for the is 30 psi according to the sticker in the trunk
Then in the back I have 225/50R16 now I keep these at 30psi aswell but I do not know if it is the right pressure for these tires. is there some way to calculate the required pressure?

capriracer

Yes, there is a way to calculate the tire pressure, but you need to have access to the tire load tables, which are copyrighted and not allowed to be published except by permission. I have a copy and I'll do the math for you:

The rear tires need to be at 35 psi.

thecardoc3

The bigger question is why is he running a smaller tire on the rear?

djd1kimpala

thecardoc3 said:

The bigger question is why is he running a smaller tire on the rear?

I bought the car with 4 225/50R16 but then one of the front tires broke. I did not have any money to buy brand new tires so I went to a used tire dealer and all they had where 225/60R16's

thecardoc3

What size tire does the car call for on that sticker?

djd1kimpala

thecardoc3 said:

What size tire does the car call for on that sticker?

The sticker calls for the 225/60R16's.

alaskanbelle

My comment is slightly related to the original post. I have a 2003 Chevrolet Impala that had 60,000 miles when I bought it,  but I'm  not sure it had the original tires. The front passenger tire kept slowly losing air pressure.  Eventually we got a brand new set of Pirelli tires per the specs of the car. Shortly after, the tire in the same location started losing air. We did NOT have the valve stem changed with the new tires. We did have our dealership check the tires, and they did the soap on the valve stem trick and said that it was fine.

My question is, what could be causing the air leak on a nearly brand new set of tires? I have to refill that tire about every 2-3 weeks. Also, my husband said that the pressure should be between 40 and 45 psi. Sure enough, when it falls to around 39 psi, the warning light comes on for the tires.  Help?

Mr_Shiftright

I think first off you should re-inflate the tires to the factory setting which would be 30-35 psi. Then I would follow the owner's manual to reset the TPMS system. Sometimes you can do this through the radio (if so equipped with the correct type of radio) or you have to use a scan tool.

45 psi is over the spec, but if you prefer a stiffer ride and don't mind the possibility of uneven tire wear, then that's your call.

The tire pressure monitor can't tell you which tire is deflating (although it sounds like you know) and it will only detect a pressure differentiation. It doesn't get set to a specific tire pressure. If all your tires were inflated to 30 psi or 50 psi, and one drops a few lbs., the same thing would happen.

I suspect you must have a rim leak of some sort--on some alloy wheels, the wheels themselves can leak--right through the metal, not the rim. The cast metal becomes porous as it ages. GM cars are known to do this, too.

This can generally be repaired with sealant.

dave6814

You have to use tire load inflation table to match new tire size weight to its psi. According to metric inflation chart if you switch from 225/60R16 at 30 psi to 225/50R16 your new psi should be 40 psi.

You can look up the values here - Metric Tire Inflation Chart