Differential Lock: Testing and Inspection

Fig. 1 Selec-Trac Diagnosis, Model 229 Transfer Case (Part 1 of 2):

Fig. 1 Selec-Trac Diagnosis, Model 229 Transfer Case (Part 2 of 2):

MODEL 229 TRANSFER CASE

1. Disconnect vacuum harness from front axle shift motor and connect suitable vacuum pump to shift motor front port.
2. Apply 15 inches vacuum to shift motor and rotate right front wheel to fully disengage axle.
3. If shift motor does not maintain vacuum for at least 30 seconds, replace motor.
4. Disconnect vacuum pump from shift motor front port and connect pump to shift motor rear port, cap transfer case connecting port and apply 15 inches vacuum to motor.
5. If shift motor does not maintain vacuum for at least 30 seconds, replace motor.
6. Remove cap from shift motor transfer case connecting port and check for vacuum at port.
7. If vacuum is not present, rotate right front wheel as necessary to ensure that axle has disengaged completely.
8. Check vacuum at shift motor transfer case connecting port again. If vacuum is now present, refer to the charts.