Chevrolet Malibu Tires / Wheels

rw08maliburw08malibu Member Posts: 8
I purchased a slightly "used" (2,700 miles) 2008 Malibu LT that has the Factory Chevy Malibu 18 inch LTZ rims with 225/50 18 tires. I was told that this was a demo car, which made sense, because it has never been never titled, and I bought it at the Chevy's dealership's used car lot. A Car fax report confirmed this. Since the LT package does not come from the factory with these rims and tires, I am assuming that original 17 inch tires and rims were removed at some point. I love the look of the shiny rims. However, since I bought this car mainly because of the fuel economy potential, I am now concerned that these tires and rims will have a negative effect on my 4 cylinder's MPG rating. Also, since the car's factory sticker located near the driver's rocker panel clearly shows 225/50 17 tires & wheels were on it from the factory, I am now worried that my speedometer and odometer will be giving me readings on MPH and MPG that are not correct. Does anyone know: 1) if the larger 18 inch tires and rims will give me less fuel economy vs the normal LT 17 inchers, and 2) does Chevy at the factory level calibrate the odometer specifically differently for the 17 inch and 18 inch tires? Thanks!


  • e_net_ridere_net_rider Member Posts: 1,380
    Go to a tire sales site at look at the specs for the two sizes involved. Either or both if shown should be the same circumference or diameter.
  • globalmktsglobalmkts Member Posts: 1
    go to:

    That will give you the RPM on wheel vs tire size. With a little math using proportion calculation ratio you'll see how many fewer RPMs, therefore distance (one RPM and tire travels 4.76' on the road for example) or 1,109.2 RPMs. Divide that into 5,280'. Then take the next tire size, do the same and see what the difference is. That will be a % which u can use to determine how much further or less travelled your tire is. Then you can calc the MPG!
  • maddog0324maddog0324 Member Posts: 55
    If the dealer installed the 18" rims & tires on the vehicle, they should have also installed the correct gear for the VSS to match the wheel/tire combination.
  • frugalskatefrugalskate Member Posts: 2
    My '08 Malibu LS has the plastic wheel covers, and they now have a lot of stains, sort of like rust, and I need a good cleaning method. So far nothing I've tried works. And if I scrub too hard, the finish wears away,leaving a bigger eyesore.
    Anyone else had this issue? If there isn't a remedy, what would be a good rReasonably priced solution?
    Thanks for your suggestions.
Sign In or Register to comment.