Inline Speed Calibrator

[bryant87]

I currently went from the factory 275/70r18s to 37x11.50r18s and my speedo is off by around 11%,  i saw Hypertech and rough country both make speed calibrators and was wondering what was the best route to go? not sure if one of these would mess with the warranty or not??

[Jay Gill]

They both use the same software and physically look the same and have the same instructions. I suspect they are both selling the same underlying unit. I bought hypertech.  Works great.  It doesn't reporgram the computer, just real time adjusts the signal on the way to the computer for speedo.  It is 2 plugs, you could always pull out in 5 minutes before going into dealer for service.

[bryant87]

thanks for the info!

[Jay Gill]

I forgot to mention, I had to download a second software (.dll I think) that wasn’t in the instructions. The software threw an error that it was missing and the software couldn’t find it. It was super easy. More annoying the instructions didn’t mention it. 

[Dalton Belcher]

What did you end up doing for the Speed calibration? And what’s your new fuel economy with the pizza cutters?

[GP9]

Is there a function to change the wheel size? Maybe someone with a scanner can change it.