Meritor MTC-4208X Series, Service Manual, Page: 99 / 120

Copyright Meritor, Inc., 2020 Printed in USA
MM-0861 / Revised July 2020
Page 95
9 Troubleshooting
Front Axle Declutch Does Not Engage/Disengage Diagnostics
Return the vehicle
to service.
Return the vehicle
to service.
Return the vehicle
to service.
Figure 9.5
Turn wheels left and right several
times, then try to shift declutch.
Check indicator light,
and engagement and
disengagement sensors
for correct operation.
Check the available air
pressure. The transfer
case requires at least
60 psi (4.14 bar) at all
times to operate correctly.
Yes
Yes
Yes
Yes
Yes
No
No
No
No
Replace faulty indicator
light or sensor, then
try to shift declutch.
Correct system air pressure.
Refer to OEM instructions.
Check the piston cylinder on the declutch.
Clean the air supply system.
Refer to OEM instructions.
Verify the transfer case shifts correctly.
Return the vehicle to service.
Check the PTO for leaks.
Reinstall the transfer case onto the
vehicle. Road test the vehicle to
confirm the problem is corrected.
No
Remove the transfer case from the vehicle.
Follow disassembly procedures.
Inspect the front axle drive gear, shaft, shift
collar, collar engagement teeth on gear, shift
fork, shift fork bore, piston, o-ring, and return
spring for damage.
Repair all damaged components.
Reassemble the transfer case.
Verify the transfer case shifts correctly.
Return the vehicle
to service.
Light or
sensor
faulty?
Air
pressure 65 psi
(4.48 bar) or
more?
Declutch
shifts
correctly?
Declutch
shifts
correctly?
Air
system
contaminated?
4001529d