For those rolling on 20's did your gas milage go down when you put them on and if so by how much? Also if anyone has them that tows can you notice a difference in power? (pulling) I have been told it will kind of change my gear ratio. Just trying to get some advice for when I get my truck back.

 

I tow a 24' Baja, 5k with trailer and mine does fine. I've got 20's, I don't know how much the MPG went down because I put the wheels/tires on when the truck was new..

 

Wheels don't change the ratios... the overal tire diameter does. If your rollin' on 16s with a 30-inch tire that's the same as rollin' on 20 with a 30-inch tire.. just a lot less sidewall. Get it? It's all about the diameter of the tire, not wheel...

 

Thinks for that I get it. What kind of gas milage do you get with the 20's?

 

Probably the same depending on the ratio of the tire... Different people get different gas mileage on how hard they drive it what size tire what alot of stuff makes differences..

 

I don't have 20s yet. But here's the other secret.. the real killer to the MPGs is the weight of the wheel/tire combo... Read this and learn a bunch..

http://www.tirerack.com/wheels/tech/...jsp?techid=108

 

thats great something else to marinade on.. anyone happen to know what the 18" fx4 wheels weigh?

 

That's info I don't have... I also need the wieght of the 18" lariat wheels.

 

That was a great write up, but it still showed that the stock tires and wheels got the best mpg. Even the lightweight wheels couldn't get the same mpg as the stock wheels.

 

Weight causes change. Rotational inertia baby.

 

On my 03 I lost about 1-2 mpg. I used a 295/45/20 to replace my 265/70/17's..
Hope that helps ya..
And it is because the new rim/tire combo weight...

 

My 24s weigh about 180lbs each (wheel and tire) and I lost about 1.5-2 MPG in the city and pretty much nothing on the road with them. The major reason for the loss of MPG in the city is the energy to get them started rolling...once they are rolling your good to go.

 

I lost about .5 mpg with mine. It went from 14 to 13.5 mpg. My new wheels and tires weigh about 80lbs/ea.

 

I went from 15.5 mpg to 13 mpg when I got 20s. Note that I did switch from the stock 30 to a 32 inch tire, and I have 3.55 gears. I'm definetly getting 4.56 gears next.

 

Probably the biggest factor is the tire width. More rubber = more drag. Get skinny tires!

Although 180 lb wheel/tire combos will also definitely kill your mileage! Holee **** RammSST!

I wish BBS made lightweight forged wheels for our trucks!