What pressure should car tires be? (1 Viewer)

[Kevin Farley]

My tire guy (and the tire itself) says to max it out at 44 (at least for my tires) and the lube guy, and other people say 32. What do you guys think? Personally, I'd say 44. But is that bad for the tire life? And what are the advantages/disadvantages?

 

[Lance Nichols]

Check your owner's Manual. Each car has it's own recomendations, and limits.

Mine recommends 32PSI, even though the tyres max @ 40PSI (Dodge Neon)

 

[Brian Perry]

If you go too high, the tread will wear unevenly (as it will if it's too low) and your suspension will wear faster due to the stiffer ride. You may see a tad better gas mileage with more air, though, so I tend to keep it on the high side of the recommended range, which is printed on the inside of my car's door. I believe mine is 33 p.s.i. for the front and 41 for the rear.

 

[Richard Travale]

look at the inside of your front driver side door. The information you need will be on a sticker.

 

[Philip Hamm]

The number on the tire itself is the max that the tire can handle, not a recommended running pressure.

What you need to pay attention to is the recommended pressures that the car maker has designated. This should be in your owner's manual, in a sticker inside the front driver's side door, or on a sticker somewhere else on the car like behind the gas cap. It will likely be different for a full car vs. empty car.

 

[Mike Lenthol]

I was under the impression that: a tire has a maximum pressure rating, and a load rating, which are related.


Say you have a tire rated 44psi and 1500lbs. If your car only puts 1000lbs on each tire, you'd pump them up to 2/3 of the 44psi.

All these 'rules of thumb' come out pretty close to each other, and it shouln't really matter either way.

 

[MarkHastings]

If you hear a loud BANG, you've put too much air in. LOL


Seriously, this site has a very comprehensive list of all car manufacturers and tire pressures:
http://www.drivegreen.com/pressureData.shtml

 

[Denward]

Do a search on 'tire pressure' in After Hours. You will find the collective wisdom of HTF on this topic. Here are a couple of threads that should be of particular interest:

http://www.hometheaterforum.com/htfo...=tire+pressure

http://www.hometheaterforum.com/htfo...=tire+pressure

 

[Ted Lee]

the second link denward posted is mine. there's some really good info in there.

be sure at least to read this post

 

[Steve Schaffer]

Kevin,

The pressure on the side of the tire is the maximum allowable before risking blowing up the tire. That same model tire can be used on any number of different vehicles with different handling and load characteristics, and that max pressure on the side of the tire is not going to be the best for any of them.

Somewhere on a sticker on a door jamb or on the inside of the glovebox door or in the owner's manual you will find the tire pressure recommendation of the car mfg. This is the tire pressure you should be using, not the generic "one fits all" max on the side of the tire. The car mfg recommended pressure is the one that will make the car ride and handle as intended by the carmaker. The car mfg has done millions of dollars worth of development on their suspension calibrations and come up with their recommended tire pressures.

Often mfgs will recommend different pressures front and rear to compensate for uneven weight distribution or to prevent tricky handling characteristics. Rear engine cars typically recommend lower pressures on the front vs the rear to help keep the rear end from swinging out in hard turns.

The infamous Chevrolet Corvair, unfairly called unsafe at any speed due to it's rear engine handling by Ralph Nader was perfectly safe if one used the factory recommended tire pressures--15-18psi front and 28-32 rear.

Most cars these days are fwd and have a severe front bias in weight distribution with as much as 65% of the weight on the front. Some mfgs, but not all, recommend higher pressures front vs rear.

Don't screw up your car's ride and handling by arbitrarily pumping them up to a max number on the side of the tire.

Depending on the type of car (sports model vs family sedan) the tire pressure recommendation may be biased toward a softer ride, so you can add a bit to the factory recommendation but never more than about 4 psi.

Keep in mind that the pressure recommendation is based on a cold tire--one that's been driven less than 5 miles or so before checking. So if the tires are hot at the time of checking, add 4 psi to the desired cold pressure.