Speedometer/Odometer issue, thought it was anold yellow box calibrator but it's actually Superlift Truspeed.

[Shipwreck]

If you are moving the truck to California, just upgrade to 37" tires. With 4.88 gears, your stock speedo will be spot on and you will want 37's to run the trails in the Sierra's anyway.

Sorry, I'm no help at all...

 

[Gman094]

If you are moving the truck to California, just upgrade to 37" tires. With 4.88 gears, your stock speedo will be spot on and you will want 37's to run the trails in the Sierra's anyway.

Sorry, I'm no help at all...

It's not off by like 5 or even 15mph, it's showing the speedo pegged at like 30-40mph. 37's might be in the future once I get through all the maintenance stuff I want to do first.