Is there a tuner you buy to adjust for new tire size

Does anyone know of a tuner or anything like that, that you can buy yourself to adjust the computer for new tire size so my speedometer and odometer won't be way off? I know I can take it somewhere and have them do it, but I'd like to get one anyways, just in case I decide to change tire size again. Thanks

 

How big are you going?

The speedometer reads high with stock tires. With 285/70/17's it is pretty much perfect. With 295/70/17's I read about 2% low. To me, it's not enough to worry about. If I went to 37's I might, but if I needed tires that big I would probably be in a Heep.

 

I was going to do 285/70/17. So I guess I'll be good. I actually have smaller than stock tires on right now nd it's way off, but I'm going to change them in a couple weeks.

 

Only one I'm aware of is the speedohealer; and I think it was a bit of an involved install (the module has to stay permanently attached). I just live with the difference, which isn't all that far off (I'm on 33's). When traveling, I'll often have waze going, which shows you your GPS speed, so will just go by whatever that says.

 

If you're running oversize tires, why worry about the odometer? It will slightly underreport your miles. For example, 36000 actual miles will show as roughly 34500. It's not much, but it beats the other way around.