Engine/Transmission (1998.5 - 2002) Speedometer input

[plongson]

Where does the speedometer get its input from (99' 4x4 NV5600)?? I'm guessing from the sensor in the rear end or from one of the wheels. What is involved in re-calibration for different tire sizes?

 

[RustyJC]

The dashboard gauges are driven by the PCM. The PCM gets its road speed input from the tone wheel on the ring gear carrier on the rear axle. Reprogramming for tire size involves updating the PCM with the new revolutions per mile information. Your dealer hooks up through the OBDII port under the front center of the dash to do this.



Rusty