Took the family (four of us) to visit Grandma in Chicagoland last weekend (~375mi from Columbus Ohio).

Tires at 44psi, ran 65-70mph using CC and had the AC on both ways.

49.7/51.0 mpg to/from Chicago - these hybrids are pretty good.

sigh, if only my trips were that direction. I go from Columbus to Annapolis (420 miles), so the terrain is a major bad thing...If I average 65-70 miles per hour I only get about 40-45 mpg, though my tires had been at 36 psi for those trips

I finally got around to inflating my tires to 41 psi. I think its made a huge improvement. My last trip I averaged 52 miles per hour (wow it took forever) and got 61 mpg. No A/C (though it was 80 degrees, I just used vent air on full blast). I was at 64 mpg for a while but then I think I hit some winds. I would infate to 44, or more, but on those long inclines down the mountains (at very fast speeds) I don't want them them to overheat and blow out? My dad told me not to infate them to max, though I wanted to!

You got some very good numbers for those speeds with A/C! I still havn't hit 3,000 miles yet on my odometer. Maybe my car is still breaking in.

Carl, how do you find the ride with 44 psi. You must have real good road surface in you neck of the woods? That is great FE. H

[quote=owlmaster08;125049] I would infate to 44, or more, but on those long inclines down the mountains (at very fast speeds) I don't want them them to overheat and blow out? quote]

Your tires actually run cooler at higher inflation pressure than the factory pressure. If you go to the tire manufacturer sites they usually have a little hint to inflate higher than normal for long highway trips. Don't worry about a blowout, you can't inflate them high enough, blowouts happen from underinflation and heat buildup.

Wayne

I aired up to 44psi the first week I got the car, so its what I am used to.

My Wife and kids did not seem to mind the ride - I70 and I65 are pretty decent highways, though some rougher portions you could feel (and see FE drop).

Thanks on the FE - plenty of opportunities to draft in a convoy of trucks using this route and most of them are going 65-70mph. I did notice most other cars were going 75mph+....

Thanks. I will make sure to go all the way to 44 psi when I can get around to it.

True. But don't be so sure that it's not POSSIBLE to inflate them high enough to risk blowout. A certain someone I know (who shall remain nameless ), inflated all 4 tires in a vehicle to about 90 PSI. This person did not have/use a gauge, so just judged it - very poorly. The complaint that resulted in this discovery was a harsh ride. I bet!
At this pressure, they could've exploded off the rims AS they were being aired up, let alone while driving.
And, no - it wasn't ME

Steve

STOP terrorism - Drive a HYBRID

Vehicles:
350 miles a week ------------ 2006 HCH II, Magnetic Pearl, w/NAVI (born on May 25, 2006)
350 miles a month ---------- 2003 Mazda Tribute ES-V6
350 miles a year (for now) - 1986 Mercedes 560SL

I have mine at 51psi (MAX on sidewall) but not for any gains in FE. I noticed little if any going from Honda' recommended tire inflation spec. The ride is a little firmer but the handling has improved... especially in the rain.

We're taking a trip to the Keys soon. We intend to get the best MPG we can (especially with gas near $3/gal. here and well above that down there). I'll check the tires to insure they're at least 40 PSI, we'll keep to the speed limit on CC, and we'll use A/C as little as possible.

Steve you are correct in your warning about over-inflation.

There may also be insurance and liability issues by knowlingly introducing an unsafe condition.

The tires should never be inflated above the maximum level imprinted on the them. Check each tire if you run different models, the rating may be different.

R. Mark Owens - Casper Desert Mist