Proper Tire Pressure?

[chrisblues]

Can someone tell me the proper tire pressure for my tires. I have people telling me 35, others says 32.5.They are the P205/55R16 All Season Tires.

[nismo]

You should keep the tire pressure somewhere between 32-36. NO MORE THAN 36 though! You'll blow a tire.Inder

[ragingfish]

GM recommends 32 psi, and I strongly urge you to inflate to 32, no more, no less...Going higher or lower can affect handling and tire wear...You can find the manufacturer recommended tire pressure on the label inside the glove box...

[Tango]

I run my tires just below the Max on the sidewall. It will protect the rim and tire from potholes at the same time. As well as give you excellent tire life! With the stock Continental Tires, I got 28,500 miles. And they still had life left as they hadn't reached the wear indicators yet.

[ragingfish]

The sidewall-indicated pressure is the maxium the tire can handle safely, but NOT the best tire pressure for your vehicle.The manufacturers engineer the cars, and know what the best pressure is for handling, safety, and most importantly, tire performance. 32 is the best you can run at with this car, and anything much higher or lower than that is only hurting yourself.

[Tango]

That is such false info! You have fallen for the company line. You will also wear your tires out much more quickly. And that is what they want! My info comes form speaking to a BMW engineer. I also worked for a Ford Dealer. We never had a problem with any complaints! But, it's your car, and your tires. If you like spending money needlessly on tires. SO be it.

[MadBill]

I'll second Mike on this: The maximum on the sidewall is for all possible applications of the tire. It has nothing to do with what's best for your car. Apart from racetrack/autocross use, stick with the vehicle spec., +2 /-0. p.s.i.g.

[Tango]

If you stick with the Vehicle spec. Then you also are stuck with the "stock" Tire. Continental. BTW I got 28.500 miles and they hadn't reached the wear indicators yet. They wore very evenly, no cupping. That's a lot more than anyone else has gotton on Continentals. Tire shop said maybe another 5,000 miles left. Rotated every 6,000 miles, and 2 four wheel alighments. I was very happy with the stock tire. Went to Falken after pricing all the major brands.

[MadBill]

OK, I've edited my entry to include "p.s.i.g.", thereby allowing a change of tire brand. Quote, originally posted by Tango »...Tire shop said maybe another 5,000 miles left...I think if you ask your tire shop about running say 45 psig on the street, they'll say it will wear out the center of the tread, lose most of the grip in the rain, ride like the springs were concrete ...

[futseal04]

You should stay with what the manufacturer states. Tire pressures are calculated at the factory with wear, ride, and suspension performance in mind. The reading on the sidewall is the absolute max that the tire can be inflated to as determined by the tire maker. Like others have said, just because you can air it up to 45# doesn't mean you should. Also, keep in mind that along with overinflation and the inevitable uneven wear comes uneven heating. With a smaller footprint comes increased heat build up which can lead to tire failure if you have high speed running. I guess that I am a part of the dealer fooled party line, as it was so eloquently stated. But, being an engineer myself, I can tell you that there are certain laws that say "you don't get something for nothing."

[ColonelPanic]

One question I do have about this: When you replace the stock tires, do you continue to use the same pressure with the new tires? Will the figure GM gives you be the same with other tires, or is it just specifically for the types/brands of tires the car was originally equipped with, and possibly the new tires will need a different pressure? Just something I've always wondered about...I usually try keep mine right around GM's recommendation. But more often than not, the tires will have 35 PSI in them after the dealer or tire shop rotates or balances the tires, so I have to let a couple of pounds out.

[MadBill]

If you 're-tire' with the stock size, the factory specs still apply. However, once you start juggling larger tire sizes and lower profiles/larger wheel diameters, you should consult a good tire store or experiment carefully. (as an extreme example, if you went from the base 205/55 x 16" to say a 215/35 x 19", and the roads of your daily commute resemble the craters of the Moon, you might go up quite a bit in pressure just to reduce the chances of denting a rim.)

[DavidPIL]

Hey all...Yeah, this whole thing about air pressure confuses me. Even taking the word from different Tire/repair shops. I bought some new Continentals from a local tire shop that mainly sells Contenentals. I went there instead of the discount chains because I've heard bad stories about how these tires are impossible to balance. I mentioned this before in an old post but they set the pressure to 44psi. Being concerned about this, I asked if that was right. The owner of the shop said, that tire should be inflatted to no less than 40psi. Honestly, the tires felt like they were floating on the road over 45 mph or so. So I reset them to 34 and it was better. THis was, I think more because I had wider tires (235) on to small of a rim (7"). Had no problems with the tires at all though.I then later upsized the wheels to 8" wide rims. Got the wheels at a discount chain. They couldn't balance one wheel and it was very noticable while driving... at 32-33psi. I then thought maybe with the more appropriate rim size, I can possibly increase the psi to more of that the first shop said. I tried the pressure up around 40. The ride was a bit too hard (though the ride wasn't hard at 44psi on the 7" rims). I did notice, however, that the balance issue of the wheels seemed to have gone away... much less wobble in the steering wheel.I run the tires at 36-38psi (cold). I have 26,000 miles on em and they're still far from being worn and seem to have no noticable uneveness in wear, except for wearing slightly more on the side closest to the car. (had the tires flipped on the rims to help even the wear).Even some tire places, like Discount Tire talk about adding a few PSI for up-sized tires/wheels as MadBill also mentioned.see next post...

[DavidPIL]

One thing you have to remember is that if you drive to a tire place, probably a few miles or so... also figuring the sun might be out, your tires, could easily add 1 or 2 PSI normally. Maybe more if you have to drive highway speeds. The PSI rating is cold... From what I've come to read, it's what the tires should be in the morning without the sun hitting them. I know for a fact that even in an open garage, my tires near the opening of the garage, though still in the shade, can be a pound higher than the front though when checked before the sun comes out, it's even.If you check your tire pressure during the day even if the car is not driven, and you set it to 32 psi, by the time the sun goes down and the daytime heat goes away, you may be 2 or 3 pounds under.As I've read here and in other places, for every 10 degree increase in ambient temp, your pressure will go up about 1 psi. So, wouldn't that be if you check the tire pressure in the afternoon, you should actually set the pressure to 34 psi because by the time the daytime heat goes away, it's liable to drop 20 degress or 2 psi?I've noticed that from standstill to after driving for 30 minutes on the highway, I could be up 4 psi. So, this is also something that needs to be taken into consideration.Setting pressure, during the day, after driving some, a tire place or whoever shouldn't set your pressure to 32 and if they do, you should definitely check it after the car has sat for a few hours after the sun goes down or in the morning before you take off. One thing I do is check the pressure at home, in the morning. See how far I am from where I want to be then if I have to drive a distance to fill em up to spec, I add what the original pressure difference was. This may, and usually does, put the pressure higher than I'm shooting for but I know that cold, it'll be more correct.I dunno if any of this makes sense but my tires are wearing great, the ride is now very comfortable.Dave

[Tango]

I think if you ask your tire shop about running say 45 psig on the street, they'll say it will wear out the center of the tread, lose most of the grip in the rain, ride like the springs were concrete ... [/QUOTE]I check my tires religiously. Especialy to see that they are wearing evenly. The tires(Falken) are rated at 51 psi. The mechanics that I deal with all say that the only harm is a harder ride. The Continentals that came with the car were rated at 44 psi. I ran them at 42 and the tires wore very evenly!

[jonathonbarton]

Tango.You *do* realize that by running your tires at 42psi that if your tire experiences a heat-related increase of pressure on the order of 5 psi you're *over* the max rated for the tire, and are risking catastrophic failure of the tire......right?Do this for me...Set your tires to 42psi, get out on the freeway, drive a dozen miles at 75mph, then stop suddenly, jump out, and check one... M'Kay?

[DavidPIL]

Hi Jonathon...The psi rating on a tire is when the tire is cold. If he sets the tires at 42 PSI in the morning or "cold" then any increase in pressure during the day due to temperature rise from normal warming or driving, although may take the pressure over the stated 44 psi, it's still not over the rated psi when cold.Checking the tire pressure during the day or after the car has been driven isn't smart because you'll get a false reading as compared to what the specs of the tire should actually be. Check out Tire Rack's info on this @ http://www.tirerack.com/tires/...ationDave

[DavidPIL]

Chris,Since you have the OEM tire on the vehicle, I would suggest following what GM recommends, which is 32 psi. But be sure you set this when the tire is cold, in the morning before the car has been driven.You could play with slightly more pressure but I don't think you should put more than 36 psi in. I seriously doubt your tires will blow out so easily if you were over 36 psi since the tire is probably rated to 44 psi. If you run em above 34-36 psi, the ride will probably be a bit less comfortable, you'll probably feel more bumps in the road. As mentioned before, If you do increase the pressure, keep an eye out for increased wear in the center of the wheel tread. I run Continental ExtremeContact tires with 36-38 psi and they're wearing much more even than my OEM Dunlops did when religiously set at 32. Dave

[gpk99]

Ran TAXI for 24 yrs....owner...and i ALWAYS ran mine max preassure....and got 60,000 miles out of my tires...always......sometimes even more.......BF Goodrich T/A's....sweet tires.

[gpk99]

Ran TAXI for 24 yrs....owner...and i ALWAYS ran mine max preassure....and got 60,000 miles out of my tires...always......sometimes even more.......

[Tango]

Tango.You *do* realize that by running your tires at 42psi that if your tire experiences a heat-related increase of pressure on the order of 5 psi you're *over* the max rated for the tire, and are risking catastrophic failure of the tire......right?Do this for me...Set your tires to 42psi, get out on the freeway, drive a dozen miles at 75mph, then stop suddenly, jump out, and check one... M'Kay?Wrong! The manufacturers build in a saftey factor. With tires, I was told 10%. If the tire sidewall says "44", That's a 48+ factor. I have never had a tire related problem following my formula. Try it for yourself. Your tires will last longer, and you will spend less replacing them so often.

[Tango]

Ran TAXI for 24 yrs....owner...and i ALWAYS ran mine max preassure....and got 60,000 miles out of my tires...always......sometimes even more.......BF Goodrich T/A's....sweet tires.Good job gpk99. You won't have any problems following that regimen.

[zionzr2]

Quote, originally posted by chrisblues »Can someone tell me the proper tire pressure for my tires. I have people telling me 35, others says 32.5.They are the P205/55R16 All Season Tires.both are correct....the fronts are 32 and the rears are 35the is a sticker in the drivers side door frame that tells you the propper pressure