Hello. I posted earlier Today about tire wear. Got me to thinking about just what is correct tire pressure. Some say to inflate to near max. pressure listed on tire whereas others say to inflate to what Volvo says in owners manual/door sticker. Big difference between each. Both my front and rear tires say 44 PSI max. However Volvo says 30 PSI front and 36 PSI rear. Which is it ? Or maybe somewhere inbetween ? I do mix of highway and local driving. Only me and my girlfriend up front in car(together we weigh aprox. 375 pounds).Never carry more then 50 pounds of stuff. Opinions, advice, and input is appreciated on this subject. Thanks.
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' 88 740GLE auto wagon nearly 202,000 and ' 87 240DL auto sedan nearly 135,000

Here's what I learned over the years: The Volvo or any mfg label is for tire pressure based on the OE size and class of the tire and handling and ride characteristics for that vehicle with stock suspension. It is a compromise between fuel economy, comfort, and handling. The pressure on the sidewall is the tire mfg's max pressure for safe use of the tire regardless of what the auto mfg says. My 88 245 uses what is now a P195-75x14 tire. P is for passenger car. If I change to a LT195-75x14 which is light truck tire, things change. But Volvo didn't contemplate that so they don't show a recommended pressure.

Yes you can reduce rolling resistance and increase mpg a little by increasing tire pressure. If you can stand the harsher ride. Personally I can't. Nowadays with the spotlight on fuel consumption I believe the recommended tp is the way to go. Sometimes I will go a couple of lbs over but I keep the same difference between front and rear. If mfg says 32 front 34 rear I will add 2 lbs to each being 34 ft and 36 rear, to maintain handling characteristics.

Ever hear of the Corvair, maligned for it's handling? Most shops and owners neglected the fact that the front [this was a rear engine rear drive car] had no weight. Recommend tp was about 18 lbs front and 32 rear. Put 32 in the front and surprise, it went right off the road in a turn because 32 lbs changed handling...
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1988 245A. Past: 1979 245A; 1987 244 M47; 1971 164E

Remember that the pressure in the tires increases when you drive, and cold pressure (after a night in the garage) is always a little lower. For that reason I never inflate to the max psi (esp when cold) because you might get over-pressure then.
I like somewhere b/w 32-36.

The standard is about 32 PSI. Nice ride but not too efficient due to the increased rolling resistance. I pump my tires to about 35-36 PSI. Anything over that gives you a bone jarring, teeth rattling ride. Inflate to much over that you get too much wear in the middle. At 32 or below, too much wear on the outside.

I have to adjust the pressure om my cars and the kids base on the wear. Usually the kids tires wearing on the outside. I wonder why? (Not really.)

Tom