Once I put my new tires on I updated the size with the programmer. Problem is when I am going 72 the spedo reads 76. In the 60's it is around 3 off. What is the easiest fix to this? BTW the speed I am comparing is from my GPS

 

just dial it in, It may take several tries, the smarty gives you all sorts of tire heights to choose from. not sure about the Hypertec. just move it up or down until it gets right.

 

Like 03RAMBUNCTIOUS said it will take a few trys but you should be able to dial it in.

 

I forget. Do I go larger with the tire size or smaller to slow down the speedo?

 

Larger size makes the speedo slower.

I took a tape measure and measured the tires while they were sitting, vice the measurement that the tire actually was.

 

Yep, and I still had to go smaller on tire size to get the speedo correct with the GPS. Ya just gotta play with it until you got it dialed in.

 

My '35's' are a 32.5...

 

Quit spinning them so much and they will stay taller.