LT to LTZ wheels

[camoweasel]

Hey everyone. Quick question?

Can I upgrade to the LTZ or RS tire/wheel combo on my LT sedan? I really like the look of the 17s over the 15'' LT wheels. My concerns:

There was a website; I think a sonic tuners website that showed the weight difference between the 15'' and 17'' wheel combos. It was a 6 pound difference. My car is averaging about 37-38 MPGs right now and will this heavier tire/wheel combo affect my gas mileage?? Also on a few tire diameter calculators the 17'' tires are few millimeters larger in diameter so will this affect my speedo as well? I'm assuming the LTs and LTZs used the same gearing so I doubt that should be a problem?? Thanks everyone!

 

[mitdr774]

They are heavier and will affect city economy a fair amount. Highway driving will have less of an affect. On the highway I see about a 0.6 MPG difference between stock 15" wheels and tires compared to LTZ wheels with 225/45/17 tires. Seeing as how I am somewhat obsessed with hitting my goal for highway economy I will not be running my LTZ wheels again until after my next trip.

 

[rdss]

I lost 2 mpg in the city but I also went up from the standard width of 205 to 225 causing more rolling resistance. I'm averaging 31-33 all city and just made my first long run to Orlando today and averaged 35 mpg but I was running 75-80 the whole way with a head wind on the way down giving me about 33 mpg on the way down. When you buy tires try and match the tire hight as close as possible, with my 225/45/17's I'm spot on the LT's tire hight. Tuning will also get your speedometer back in line if it is off.

 

[laborsmith]

And one loses millimeters as one drives and wears the tire down.

You will have no problems making the change.


Laborsmith

 

[wingman]

It will be minimal mpg loss. I can still hit well over 40 in the city if I try. I am tuned with intake and turbo back on 225/45/17's. I average about 35-36 combined and have fun/look good doing it.