ECM Calibrator

The Rough Country Speedometer Calibrator is an easy-to-use device that allows you to reprogram your vehicle's speedometer to match the output of larger tires. When upgrading to larger tires, a discrepancy can occur between your actual speed and the speedometer's reading. This plug-and-play device connects directly to your vehicle's Diagnostic Link Connector Port, recalibrating your speedometer in minutes. Beyond just the in-dash readout, this calibrator updates your vehicle's ECM to ensure accurate shift points and proper electronic stability control functionality with larger tires. It offers an affordable and intuitive setup process. A useful feature is the ability to reset the speedometer back to stock settings, which is beneficial prior to servicing the vehicle. The device comes with a 1-year warranty. This speedometer calibrator fits gas and diesel 1500, 2500, and 3500 models. It is designed as a standalone unit and is not compatible with any other performance programmer. Once programmed to a vehicle, the device is locked to that specific vehicle until it is returned to stock settings. It does not fit 2022 refresh models or 2022 Chevy/GMC refresh models with specific frontend styles. It is also not for sale or use in California.