ROUGH COUNTRY Speedometer Calibrator Gas | Ram 1500 | Jeep Wrangler | Dodge Ram 1500

The Rough Country Speedometer Calibrator is the definitive solution to correct the speedometer and odometer readings on your gas Ram 1500, Jeep Wrangler or Dodge Ram after installing larger tires or regearing the differential.

Larger tires throw off the factory speed reading, which affects the odometer, transmission shift points and ABS system. This calibrator corrects all those parameters in minutes through the OBD-II port.

• Plug & Play: direct OBD-II connection, no splicing required.
• Compatible with tires from 28" up to 41" in diameter.
• Axle ratio adjustment to reprogram the ECU after regearing.
• Read and clear trouble codes and Check Engine light.
• Real-time monitoring of engine parameters (RPM, temperature, voltage and more).

Installation in under 5 minutes: plug it in, select your vehicle, enter the tire size and axle ratio, and you are done. No shop or expensive diagnostic tools needed.

An essential addition after any suspension lift with oversized tires. Built and backed by Rough Country.

Download installation instructions (PDF)