After upgrading your vehicle to larger wheels and tires with a suspension lift kit causes the speedometer to read correctly. This can be easily taken care of with the Flashcal F5 Programmer by Superchips. This easy to use calibration tool is a hand held unit that has a bright and simply to read 2.8" Color screen. The Flashcal plugs into the ODB port in all Wrangler JL vehicles and can calibrate a number of features for the Jeep. Read and clear diagnostic codes, correct speedometer for tire upgrades (between 25"-40"), calibrate for gear or axle swaps, DRL on/off, and many more features. This complete setup for the Wrangler JL includes a Jumper Module that is necessary for the installation. Explore all that the Jeep has to offer with the Flashcal F5 Programmer.