Now there’s a simple plug-in device that makes your automatic overdrive transmission really perform. TransTuner™ increases line pressure and shift firmness, eliminates expensive valve bodywork,...

Accurately calibrate today’s electronically controlled speedometers for 1994-current GM cars, trucks and SUVs. Now there is a simple way to correct for unwanted speedometer error caused by wheel...

Virtually every vehicle manufactured since 1992 is equipped with an electronic speedometer that uses a sensor to read vehicle speed rather than a mechanical cable. This speed signal is a big...