Removal and installation
1. Disconnect the negative cable from the battery.
2. Jack up the rear of the vehicle and place it on jack stands.
3. Working under the vehicle, disconnect the wiring from the speedometer sensor (the location of the sensor is shown in the accompanying illustration - the inset shows the location of the connector terminals).
1 - transfer case; 2 - sensor
3. Place a suitable container under the extension housing to collect oil that may leak when the sensor is removed from the transfer case.
4. Inspect the drive gear teeth for signs of wear, chipping, or other damage. Replace if necessary.
Installation is in the reverse order.
Functional check
1. Connect a voltmeter to the electrical connector terminals.
2. Set the meter to AC voltage measurement mode, quickly turn the speedometer drive clockwise and read the voltmeter reading.
3. The result should be about 0.5V.
4. If necessary, replace the sensor.