How Do You Adjust The Speedometer For Tire Size

[GDSQDCR]

Hello

 

Just as the title says, how can I adjust the speedometer for the a different than stock tire size. From my reading here, a tune should do it, but I don't want to have to buy a tuner just for that ... so where can i go?

 

I have a 2004 Sierra z71. Current tires on it are a 265/65/18 on a 2008 Denali chrome rim. The tires are about gone and I have been looking at buying a new set. The new set will be BFG All-Terrains. I found a nice deal on a set of 285/65/18, but that is going to affect my speedometer and I would rather have it accurate. So how can I do that?

 

Second question, ... the 285 will fit on the stock 08 Denali rim, right?

 

Thanks!

Anthony

[superjim]

Your local dealer can do it with the TECH 2.

 

But depending on what he charges, I might seriously look at a Diablo Predator or a tune.