03 cav....5speed.... zero options...

What tire pressure should 14" stock tires be set at? Dealership recently set them all at 22PSI .... seems low considering the max on the tire is around 40PSI ...

Any thoughts?

Door jam said 30 psi cold temp

so i pu tin 30 PSI and it was +3C outside...

by cold pressure they mean the the temperature of the tires before they get warm from driving on them. 30 psi is correct for that car.



Injection is nice but id rather be BLOWN!

I run my fronts at 30psi, and the rears at 27-8psi. There's little weigh on the rear, thus my lower pressure AND it rides a lot better and dosen't slam you on the potholes.
Don

Don Austin wrote:I run my fronts at 30psi, and the rears at 27-8psi. There's little weigh on the rear, thus my lower pressure AND it rides a lot better and dosen't slam you on the potholes.
Don

GM already took that into consideration... why would you want to underinflate your tires, besides loosing gas mileage you also wear the outside edges more.

I ran 30PSI all the time on my 16" RS-A's and they wore perfectly even, and the ride is fine. Gas mileage is about 28mpg mixed, 32 on roadtrips to San Diego @ 85MPH

Well Rob, if you ever had the car on scales you would see that most of the weight is on the front and the rear isn't carrying much at all. I've had mine on scales and it has approx 66% of the wieght on the front. My tires wear perfectly even at the pressures i stated (no outside edge wear) AND i get excellent milage too. I get 32 in the city back & forth to work and 41 on the highway. It rides a lot better with the lower pressure in the rear's as well. When GM specifies tire pressures they usually use the highest required pressure to carry the weight on the heavy end, thus the 30 psi. The more pressure (up to the tire max) the more load a tire will carry. (I have an engineering degree, following the math isn't a problem). Do what you want, i know what works for me.
Don

Good for you mister "I'm self-consious about how fcuking heavy my car is so I'll weigh it to caluclate the exact weight bias of the vehicle so I sound cool because I know that my FRONT WHEEL DRIVE CAR carries more weight up front than in the rear." Have you weight your car with one person in it? What about two? Four? You know that front passengers sit at about the mid-point of the car, and the rear passengers sit almost over the rear axle. And one passenger can weigh almost as much as the whole engine. Two or three, you're probably carrying more weight on the rear now. Anything in the trunk?

I'll stick with what the ENGINEERS decided over what some random person on the forums posted. And it doesn't take an engineering deree to know that more PSI=more weight.

I am majoring in Mechanical Engineering, I know math also. Thanks for that little "I'm smarter than you so HMPH." You sound like a child trying to be an elitest.

I'm also a sale associate for Goodyear, you know, the people that make the tires that go on our cars. I have taken plenty of training courses on tires, wheels, air pressures, TPMS, tread design

Not that you aren't credible... I just tend to side with the people with higher education that design cars. Not to mention it 'says' you have 17" wheel in your profile... I'm assuming you used to have 14's?

And I very seriously doubt you get 41 on the highway. That's what my 07 Corolla gets if I drive 65mph all freeway, no GM will ever get that (maybe the Aveo on an amazing day). I have a 5 speed eco, and my mom has a 4 speed eco, and the best I've ever seen is 65mph DOWN hill from Reno getting about 37.

No need to overexaggerate... unless you just don't know how to calculate gas mileage... in which case you might need to return to high school pre-algebra -- they have refresher courses. I'm going to call bullshiet on this one.


And point two.

I work at Goodyear, probably upwards of 75% of tires I see aren't worn perfectly even, so I'm going to call bullshiet on that one too, especially if you're underinflating them. 2 psi is a lot once the tire warms up. You car is an 03? It's possible you haven't even used one set of tires yet... Maybe some proof that underinflation, a WELL PROVEN cause of outside edge wear, didn't cause any harm?

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Now back to Crazy Dude's post. Run what it says in the owner's manual / on the door sticker. 30psi.

the stickers in the door jams are ur friends so read them , if u can read


ShowOff Customz
03 Cavalier
73 Beetle
68 Fairlane 500

Well Rob, i think i stated that i'm an engineer with 20+ years of experience in the field so i have a good grasp of engineering. If i'm not mistaken, your a student learing about engineering that's currently a tire salesman?
Good comparison. My milage is as i stated, there are other posts on this site that got within 1 mpg of the same figures i stated. Milage depends greatly upon how you drive, maybe you should get some tipe from someone older to get better milage. Being a tire guy, and having seen so many tires that wear un-evenly you should know that tire pressure AND
front end alignment have a lot to do that that as well. In my 30+ years of driving, i've worn out a lot more tires than you have and always kept my cars in alignment and good tune, thus my good mileage. I gave my opion from my experience,
and background in engineering. Your smart-assed response can go where the sun dosen't shine mister.
Stick it punk.
Don

Oh, i thught i'd add that i weigh some of my cars 'cause i'm at the Atlanta NASCAR track with the late model sportsman teams as i'm one of the crew-chiefs for the teams. While they got them open and your waiting it's worth a few minutes to just see.
Don

Congratulations, mister "I'm-better-than-you." I'm so happy to share the forum with you.

All everyone, except you, has stated is to go with the door sticker.

Maybe you're elitest attitude won't convince people to go against what the manufacturer tells them. It's not thinking outside the box. He doesn't race his car (he has 14's for god's sake) so there's no necessity for fine tuning the tire pressure, he just wants to know the proper tire pressure. No need to turn this into a flamefest.


And as a side note, high psi will decrease rolling resistance, hence increasing gas mileage. Oveinflated tires cause the center to contact the road more than the edges, so less of the tire actually contacts the road. Underinflated tires cause excessive drag, i.e. increased rolling-resistance and lower gas mileage.

There's nothing wrong with going with the mfg's specs. I deviate from those because it works for me, and was offering that because it works for me. Everyone has their opinion, and that's ok. Basically calling me a liar because your experience with gas milage..etc didnt' agree with mine is what cranked my tractor. My car isn't stock, and what mods i've done have increased the milage and ever so slightly the power. A CAI, header, cat-back exhaust, mobile 1 synthetic oil, Trick shift synthetic trans fluid all contribute to that. As far as being an "elitist" , i don't think so but i've seen and done what i said i did. I've been modifying cars since my first car i got in 1974, and been an Engineer since 1983. The only point i want to end with is: "Don't discount something because you didn't do it or have that experience, someone else may have been able to get it to work".
Don