Wheel question

[kevfish1]

I am thinking of purchasing a 2005 Chevy suburban that has the upgrade of 20 inch tires and rims. Does this effect gas mileage? if so how?. Also will the speedometer still be acurate? Also will I have a problem with slush accumalation rubbing on the tires?

[Jeremy airjer W]

Not to mention the decrease in brake performance if they brakes where not upgraded to handle the new wheels. Handling will also be affected. Don't be surprised to find out the wheels are junk after running through a couple of Minnesota winters. Especially if they are chrome. Then there is the added where and tear on the suspension from riding on larger rims.

There a can of worms!

[CoorsCaptain]

Bigger rims doesn't mean bigger tires. The tires will have a lower profile than a stock rim and tire. The diameter could even be smaller with the 20's. You can google metric tire conversion calculator. Then input the tire size of stock and the 20's to convert it to inches. Then you will know how tall and wide each tire is.

[Valv]

You need to look at the total diameter of the wheel, if it's the same of a stock 17" wheel, you will not have any issue with speed or gearing.

A 20" wheel will have lower profile tires, which transforms into stiffer but more precise handling. On a SUV or truck this might be a disadvantage if you do a lot of offroad traveling, and will put your suspension under higher stress. The high profile tire will use the sidewall and the air inside to absorb shocks, and it's easier on your suspension.

For city driving there's not much importance, except for "pothole season", that's when you'll have a higher risk to crack your rims if you have low profile tires.

20" tires will have a much higher cost to purchase if you need to replace.