These pages are intended to answer the most common questions and help you solve the most common problems with differential and axle identification, repair, setup, modification and problem diagnosis. If you don’t find the technical help that you need on these pages, contact us, and talk to a differential and axle expert.
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The ProCal Module is an easy way for Jeep Wrangler JK owners to correct the speedometer and shift points when larger tires are installed and gear ratios have been changed.
The Procal Module provides functions for large tire recalibration, axle gear ratio recalibration, tire pressure monitor recalibration, daytime running lamp activation/deactivation, one -touch turn signal activation-deactivation, engine idle speed options and precise steering wheel centering. These functions are available for all JK Wranglers including the new 2012 models. Owners of earlier versions of the ProCal can send their module in for a re-flash, updating software for use with 2012 model JK's.
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