Fuel mileage?!?
Fuel mileage?!? Its seem like my car is getting worse fuel mileage than it was. I was getting right around 275 miles on a tank now its like 250-255??? The only thing different here lately is Koni shocks, lowering springs, 18" C6's, and 275/35/18 BFG tires. Could the bigger tires or rims make that much difference? I was on the 16" with like 245/??/16 tires. Could air pressure be causing the fuel mileage to go down??? I have the front at 32lbs and the rear at 30lbs. Any help is really appreciated. Thanks! 
What does that break down into miles per gallon? I don't remember the tank capacity. Keep in mind that GM itself rated these cars anywhere from 17 to 25 mpg. Also, increasing wheel size 2" probably has alot to do with it...
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From: Decatur, TN (N-W of Athens)
Yes, bigger rims suck more gas. Tire pressure does too, but only if the are low. Different tire sizes use different amounts of pressure, so you can't compare PSI between tire sizes.
I have a 2002 WS6 and going from Pittsburgh to the beach twice this year in it, I am averaging about 27.8 MPG. Pretty happey with it being that my Xterra Gets 17.5 MPG. And this MPG is while I during the trips down I walked all over a Mustang GT and on the way back the second time I walked a 04 Cobra.. So I wasn't just going 65 and letting it be. I averaged probably around 70-75 MPH
