A budy of mine got pulled over for doing 73 when his speedometer said 62 and got a $75 fine so he needs to get it fixed,so whats the best way to fix it on a 97 12v
thanks

 

he must have big tires..... there is a gear/sensor on the rear driver side of the tail shaft. mine was black. it'll have a bolt to the right of it if i recall correctly that applies pressure to a "fork" that pushes on the sensor to hold it in place. depending on what gears he has he might be able to get a different one and see if that makes it closer. if he has 3.54's then he could get one from a 4.11 truck and it'll be alot closer with those tires (assuming it is them causing it) if not i bet you can call Dave at Goerend Brothers Transmissions and he can tell you the proper way. he went over it with me and i can't remember what all he said exactly. www.goerend.com

hope this helps

 

ok thanks,ya he has 35s

 

TS Performance also sells a product called "Respeed" that corrects for tire size.

 

1190102 is the part number for it, the respeed, for his truck. the only downside to me is it is showing MSRP of $299

 

Didnt know that.

 

Have him measure the height of his tires and find out what gears he has (3.54, 4.10) and I'll run the numbers and give you a part number for the speedo gear to correct it, it may not be perfect, but we should be able to get him withing 2mph. The replacement gears are about $7 online or he can get it from a local dealer for under $20.

....Josh