lol, I'm so stupid. about a month or two ago I posted in here whining that I wasn't getting very good gas mileage. Well yesterday, out of sheer luck I went to a valvoline and asked them to make sure my tire pressure was alright. Apparently, my stock tires are supposed to be inflated up to 40 PSi, and ever since I've had the car they've been inflated to 32 PSi? I said to the guy after giving him a blank stare that I've always filled them up to 32 ever since I bought it in October. He told me the tires said 40 or 44 PSi? somewhere inbetween there. Anyways, I get back on the road and head towards the highway and noticed a HUGE difference in handling and gas mileage. I can't believe I was being so stupid before[:@] I donno, I thought I'd share and maybe help somebody who thinks they have a problem but in actuality only need to put some air in their tires

 

Actually 32psi is what they're supposed to be at. But you should check them when it gets cold because the pressure changes.

 

Yeah I always put them at 32 to 35, because while driving, air pressure goes up because the tires heat up. When air heats up, it expands. And I belive that 40 to 44 is maximum.

 

You never want to inflate your tires to the MAX rating on the tread, why, here are some of the reasons:

1.) Risk of improper tire wear from over inflation (+/- 4psi under warm and/or cold weather)
2.) Does not leave much room for play in the side walls which could cause damage (if you have pot holes like I do! )
3.) Tires should "technically" be filled OFF the car/truck/whatever and not with the weight of the vehicle so pushing them to the max is more than likely pushing them over the limits
4.) Like stated before, the Manufacturer sets the amount of air the tires should have, not the TIRE manufacturer. They have to rate them a little higher b/c the size may fit on a multitude of vehicles (not exclusive).


The ONLY reason I know this much about tires is b/c of 3.5 years of working (and being certified) in a tire shop and many training classes by BF Goodrich.

Always go by the door jam sticker.

Hope this helps!

ehorizon7

 

so wait... shoud I let the pressure out back to 32-34 psi or is 40 bad or what? now i'm affraid that my tires are gonna blow up

 

Ehorizon7 is correct. I have had several instructors at school got conned into believing the sidewall of the tires pressure is correct. But upon further review it will tell you to use the manufacturers recommended pressure. IE 32 PSI! As far as being done off the car??? well the air pressure is not there to hold the car up but to support the belts which hold the car up believe it or not from the top of the tire. Yes the car wil ride different with more air pressure. You should have seen the car i drove into the shop with 120+ PSI in the tires. Rode like crap!!! Rode just fine at specification.

One caviot to the pressure thing is that most manufacturers actuall specify lower than optimal pressure for softer more comfortable ride. If you go to LO PRO tire you can run more pressure efectively.

 

that's it! i'm going out there tomorrow and letting air out slowly before I need 4 brand new tires!

 

Also check tires with another tire gauge some can be off a lot. Never use that thing at the gas station (YUCK)