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what is proper inflation for car tires -- with & without snow chains/cables

I have often wondered what is the proper inflation for car tires -- my owners manual says to inflate to 30 or 32 psi. I have a Honda Civic. However, the tires I have on the car allow for inflation as high as 44psi (I am pretty sure).



I often read that underinflated tires will give one poorer gas mileage. Does that mean I should inflate more than the 30-32psi recommended by the owners manual.



Now I am planning to go to the snow and have to put snow cables on possibly. One person at the Honda parts place, said I shoud inflate the tires close to the maximum to get more coverage on the road.



But is inflating tires closer to the maximum "unsafe" for a car my size. Or will it just give me a rougher ride? And will the cable-type chains be harder to put on, on a tire that is inflated "more" versus "less".



And for regular driving -- will I get better mileage if I inflate my tires more than 30-32psi?



does anybody really know the answer? thanks
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Comments

  • edited January 2008
    Inflate them to what's in the owner's manual or on the placard that should be in one of the doorjams. You can inflate them a little bit more than that to slightly improve gas mileage, but your ride quality might suffer.

    I'm not sure what the Honda guy's talking about-- overinflating the tires reduces the contact patch so that would be the opposite of what he says. Letting most of the air out of a tire is an old off-roading trick that can help get a truck out of deep mud or snow by increasing the amount of contact area-- not something you should attempt with your Honda! There's no pressure adjustment necessary for mounting chains.
  • edited January 2008
    Follow the recommended ranges by your manual. Required pressures vary depending on the size(weight) of the vehicle not the tire. Underinflated tires will give poorer gas mileage/uneven tire wear. Overinflated tires may give slightly better mileage but tires will wear unevenly/faster, give a rougher ride, and may accentuate any alignment problem(s) which may make the car unstable. Cable chains installation will not change with inflation, but you don't need to adjust the pressure for the winter either. 30-32psi cold if that's what it says, stick with it, it will give you the best balance of wear, traction, and control for your car.
  • edited January 2008
    My suggestion is to go by the tires that are installed on the car, a inflated pressure will give you a stiffer ride but may increase your fuel milage. Lowering the pressure will give you a softer ride but less steering response and lower fuel mileage. Keep it within the recommended pressure on the side of the tire and watch the tread ware. I keep mine about 1-2 LBS below what the max pressure listed on the tire side, for fuel milage. Can't help you with the chains, sorry
  • edited January 2008
    You only inflate to maximum when you have a pickup filled to maximum. Maybe not even then. Then there are overloaded ones that need the pressure. Use the sticker on your door or door frame as a guide. Then you have to use your judgement. You want to use the higher NORMAL pressure with chains but it is by no means a requirement.
  • edited January 2008
    The number(s) in the owner's manual is correct for your car assuming you have the same size tyre.

    Snow, chains or cables do not make a difference. In the old days (pre-radial) you might have lowered the pressure for snow. Don't do it today.

    The number on the side of the tyres is the MAXimum the tyres can safely hold. If your manual calls for more it means those tyres are not safe for your car.

    No number is exact. No gauge is 100% accurate. If in doubt add a couple of extra PSI. Going a little over is far less danger than going a few under.
  • edited January 2008
    The pressure that's seen on the sidewall of a tire is the MAX pressure that the tire manufacturer recommends for that tire. That's because that tire can be used on many different kinds of vehicles. So while one vehicle may have a tire pressure recommendation from the vehicle manufacturer, when applied to another vehicle, the tire pressure recommendation from that manufacturer might be different. So the tire manufacturer designs that tire to be applied to many different kinds of vehicles.

    Vehicle manufacturers run extensive tests to determine what tire pressures should be used to provide the best ride, handling, safety, and tire life when those tires are used on that vehicle. And this is why you always follow the recommended tire pressures that the vehicle manufacturer recommends.

    Tester
  • edited January 2008
    Interesting all your comments, but I have a Caravan 2002 that seems to be always low of pressure from the front tyres. And the edges are worn out...I am rasing 3 or 4 PSI more since I noticed it.. I am not sure if I am doing the right thing. Ahy comment about??
  • edited January 2008
    Sure. You can adjust the tire pressures up 2-3 PSI from the recommended pressures to see if it helps with tire wear. But don't rule out that the tires are leaking air or that the front end is out of alignment causing the tire wear. Also, the Chrysler mini-vans are little front heavy along with a high center of gravity. This can cause tire scrubbing while cornering causing the outside tread of the tires to wear faster.

    Tester
  • edited January 2008
    ....Seems tire pressure is always low in front, leads me to suggest the alloy wheels need refurbishing/bead cleaning or replacing if the bead continues to leak.
  • edited January 2008
    Inflate your tires to the 30-32psi recommended by the owner's manual. Anyone who tells you anything that contradicts your owner's manual is misinformed.
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