31/05/2024 10:40:57
Subframe Assembly - Rear (Remove and Install)
Correction Code 30010201
- 2023-09-07: Updated links for 12V power disconnect and vehicle electrical isolation procedure.
- 2023-06-21: Updated note for replacement of seized rear drive unit HV harness.
Note
Loosen suspension fasteners by hand, then use a cordless electric drill with a 3/8 in drive adapter and a 3/8 in drive air ratchet wrench.
Warning
Only technicians who have been
trained in High Voltage Awareness and have completed all required certification
courses (if applicable) are permitted to perform this procedure. Proper personal
protective equipment (PPE) and insulating HV gloves with a minimum rating of
class 0 (1000V) must be worn any time a high voltage cable is handled. Refer to
Tech Note TN-15-92-003, "High Voltage Awareness Care Points"
for additional safety information.
Warning
If the vehicle has air
suspension, activate "Jack" mode on the touchscreen before raising and
supporting the vehicle.
Warning
If the 12V power
supply is disconnected, do not attempt to open any doors with door glass in
closed position. Failure to follow this instruction could result in door glass
shatter.
Note
Before
disconnecting the 12V power supply, ensure that the driver’s door window is
fully open. Failure to follow this instruction could result in vehicle
lockout.
Small RDU
Remove
-
Prepare the vehicle for lifting:
- Air suspension vehicles only: Put the vehicle into Jack mode.
- Put the vehicle into Tow mode.
- Support the vehicle, but do not lift it at this time.
- Disconnect 12V power. See Disconnect 12V Power.
- Perform a vehicle HV disablement check. See Vehicle HV Disablement Procedure.
- Remove the rear wheels. See Wheel Assembly (Remove and Install).
- Raise the vehicle to working height.
-
On both sides of the vehicle, remove the nut that secures the shock absorber to the knuckle (torque 140 Nm), but do not remove the bolt yet.
-
On both sides of the vehicle, loosen the bolts (x2) that secure the brake caliper to the knuckle (torque 120 Nm). Remove and support the calipers.
CAUTIONTo avoid damage to the brake line, the brake caliper must be supported at all times.
-
Release the red locking tabs, and then disconnect the electrical harnesses from the LH and RH parking brake connectors.
- Remove the mid aero shield (refer to procedure).
-
Remove the subframe shear plates by removing the nut (torque 35 Nm), clips (x2), and screws (x3) (torque 6 Nm) that secure each shear plate to the subframe.
-
If equipped, remove the screws (x2) that secure the rear skid plate to the subframe (torque 10 Nm).
-
Disconnect the subframe harnesses from the body harness.
- Vehicles built through September 2014: 4 connectors at the back of the rear subframe
- Vehicles built after September 2014: 3 connectors above the RH side of the rear undershield
- On the RH side of the drive unit, disconnect the logic connector.
- Remove and discard the 4 screws that retain the HV cables (torque 7 Nm). Move the cables away from the drive unit.
- On the top RH side of the drive unit, release the ground strap from the drive unit (torque 6.5 Nm).
-
Release the clips that secure the HV cables:
-
Remove the coolant hoses from the LH and RH sides of the drive unit.
- If the drive unit is being removed, drain the gearbox fluid. See Gearbox Fluid - Rear Small Drive Unit (Drain and Refill).
- Position the powertrain table with subframe fixture beneath the vehicle subframe.
- Connect shop air to the powertrain table.
- Carefully raise the powertrain table to support the rear subframe, aligning the subframe fixture dowels with the holes at the front of the subframe.
- Use a paint pen to trace around each subframe mounting bolt, so that the bolts can be realigned later during the subframe installation.
-
Use a paint pen to apply witness marks where the front/rear subframe contacts the body at each subframe mounting bolt, so that the subframe can be realigned to the body later during subframe installation.
NoteApply the witness marks at 90 degrees so that they indicate left/right and fore/aft movement.
-
Remove the bolts (x4) that secure the rear subframe to the body (torque 140 Nm).
-
Carefully lower the powertrain table approximately 3 in (75 mm) to gain access to the remaining attachments.
CAUTIONWhile lowering the table, occasionally stop to make sure no hoses, harnesses, or other components are caught or tangled. Also pay extra attention to the HV battery aero shield mounting tabs.
-
Carefully lower the powertrain table.
CAUTIONWhile raising the vehicle, have an assistant monitor the underside of the vehicle. Ensure that no components are still connected and that there is sufficient clearance so that no components are damaged.
- Move the powertrain table with subframe away from the vehicle.
Install
-
Pull on the inner halfshaft cup to confirm that the LH and RH rear drive unit halfshafts are fully seated on the rear drive unit, and that the circlip is locked into place.
NoteIf the halfshaft detaches from the rear drive unit, then reinstall the halfshaft paying attention to the following:
- Take care not to damage or displace the oil seals.
- Make sure that the opening of the snap rings are facing towards the bottom of the drive unit.
- Carefully push the halfshaft into the drive unit until there is an audible "click" from the halfshaft stub contacting the pinion shaft.
- There will be a slight pulling sensation on the halfshaft as the halfshaft circlip locks into place.
- Pull on the inner halfshaft cup to confirm that the circlip is locked into place.
- Move the powertrain table with subframe to under the vehicle.
-
Carefully raise the powertrain table.
CAUTIONWhile raising the table, have an assistant monitor the underside of the vehicle. Make sure that there is sufficient clearance so that no components are damaged.
-
Carefully raise the powertrain table so that the rear subframe is up against the body.
CAUTIONWhile raising the table, occasionally stop to make sure no hoses, harnesses, or other components are caught or crushed. Also pay extra attention to the HV battery aero shield mounting tabs.
-
Install and hand-tighten the bolts (x4) that secure the rear subframe to the body (torque 140 Nm).
-
Use a crowbar to shimmy the rear subframe with respect to the body, so that the subframe mounting bolts are centered in the tracings, and the witness marks where the subframe contacts the body align.
NoteIt might be necessary to align one corner and tighten the bolt, align the opposite corner and tighten the bolt, and so on in a criss-cross pattern.
- Torque the bolts (x4) that secure the rear subframe to the body (torque 140 Nm).
- Lower the powertrain table and move it out from under the vehicle.
- If the drive unit was removed, refill the gearbox fluid. See Gearbox Fluid - Rear Small Drive Unit (Drain and Refill).
-
Install the coolant hoses to the LH and RH sides of the drive unit.
-
Fasten the clips that secure the HV cables:
-
Perform the following substeps on the drive unit:
- Install new O-rings (1003784-00-A or later) on the drive inverter cover and apply Silicone Lubricant (1010251-00-A) on both before installing the cover. Insert the cover at an angle to prevent damage to the O-rings. Once the left (B+) O-ring is seated, rotate the cover into position.
-
Connect the subframe harnesses to the body harness.
- Vehicles built through September 2014: 4 connectors at the back of the rear subframe
- Vehicles built after September 2014: 3 connectors above the RH side of the rear undershield
-
If equipped, install the rear skid plate to the rear subframe, and then install the screws (x2) that secure the skid plate to the subframe (torque 10 Nm).
-
Install the subframe shear plates to the subframe, fasten the clips (x2), and then install the nut (torque 35 Nm) and screws (x3) (torque 6 Nm) that secure each shear plate to the subframe.
- Install the mid aero shield (refer to procedure).
-
Connect the electrical harnesses to the LH and RH parking brake connectors and then fasten the red locking tabs to secure the connectors.
- Install the plastic park brake connector covers.
-
On both sides of the vehicle, install the rear brake calipers to the rear knuckles, and then install the bolts (x2) that secure each caliper to each knuckle (torque 120 Nm).
CAUTIONTo avoid damage to the brake line, the brake caliper must be supported at all times.
-
On both sides of the vehicle, install and hand-tighten the nut that secures the rear shock absorber to the rear knuckle.
- Remove the bolt that attaches the LH rear brake rotor to the hub.
- Install the hub jack adapter onto the LH rear hub and hand-tighten the lug nuts.
- Use an underhoist stand to support the hub jack adapter.
- Measure the distance between the bottom of the quarter panel and the center of the rear axle to make sure that the rear suspension is set to ride height.
- Tighten the bolt and nut that attach the LH rear shock absorber to the LH rear knuckle (torque 140 Nm), and then mark the bolt and nut with a paint pen.
- Remove the underhoist stand from underneath the LH rear suspension.
- Remove the lug nuts that attach the hub jack adapter, and then remove the hub jack adapter from the hub.
- Install the bolt that attaches the LH rear brake rotor to the hub.
- Repeat step x through y for the RH side of the vehicle.
- Install the rear wheels. See Wheel Assembly (Remove and Install).
- Connect 12V power. See Disconnect 12V Power.
-
Perform a coolant air purge and top off the coolant.
- Remove the vehicle from the 2-post lift.
- Refer to the Alignment Requirement tables to determine whether an EPAS alignment check (EC) or four wheel alignment check (AC) is necessary. If performed, add the alignment check/adjust as a separate activity. See Alignment Requirement - Suspension.
Large RDU
Remove
-
Prepare the vehicle for lifting:
- Air suspension vehicles only: Put the vehicle into Jack mode.
- Put the vehicle into Tow mode.
- Support the vehicle, but do not lift it at this time.
- Disconnect 12V power. See Disconnect 12V Power.
-
Verify correct operation of
the multimeter.
NoteSet multimeter to DC voltage. Confirm multimeter is properly measuring voltage by testing the 12v battery.
- Remove the rear wheels. See Wheel Assembly (Remove and Install).
- Raise the vehicle to working height.
-
On both sides of the vehicle, remove the nut that secures the shock absorber to the knuckle (torque 140 Nm), but do not remove the bolt yet.
-
On both sides of the vehicle, loosen the bolts (x2) that secure the brake caliper to the knuckle (torque 120 Nm). Remove and support the calipers.
CAUTIONTo avoid damage to the brake line, the brake caliper must be supported at all times.
-
Release the red locking tabs, and then disconnect the electrical harnesses from the LH and RH parking brake connectors.
-
Remove the LH and RH subframe
shear plates by removing the nut (torque 35 Nm), clips (x2), and screws (x3)
(torque 6 Nm) that attach each shear plate to the subframe.
- Remove the mid aero shield panel. See Panel - Aero Shield - Mid (Remove and Replace).
-
On both sides of the vehicle,
remove the nuts (x3) that attach the mid aeroshield reinforcement.
NoteNuts 10mm, torque 6 Nm.
-
If equipped, remove the screws (x2) that secure the rear skid plate to the subframe (torque 10 Nm).
-
Disconnect the subframe harnesses from the body harness.
- Vehicles built through September 2014: 4 connectors at the back of the rear subframe
- Vehicles built after September 2014: 3 connectors above the RH side of the rear undershield
- Perform a vehicle HV disabelement check at the rear drive unit inverter. See Checking for High Voltage at the Drive Inverter.
- Remove and discard the 2 fasteners that secure the HV cables to the drive unit (torque 9 Nm). Do not remove the cables at this time.
-
Release the clips that secure the HV cables:
-
Remove the coolant hose from the LH and RH sides of the drive unit.
- Use a paint pen to trace around each subframe mounting bolt, so that the bolts can be realigned later during installation of the subframe.
- Position the powertrain table with subframe fixture beneath the vehicle subframe.
- If the drive unit is being removed, drain the gearbox fluid. See Gearbox Fluid - Large Rear Drive Unit (Remove and Replace).
- Connect shop air to the powertrain table.
- Carefully raise the powertrain table to support the rear subframe, aligning the subframe fixture dowels with the holes at the front of the subframe.
-
Use a paint pen to apply witness marks where the front/rear subframe contacts the body at each subframe mounting bolt, so that the subframe can be realigned to the body later during subframe installation.
NoteApply the witness marks at 90 degrees so that they indicate left/right and fore/aft movement.
-
Remove the bolts (x4) that
attach the rear subframe to the body (torque 140 Nm).
-
Carefully lower the powertrain table approximately 3 in (75 mm) to gain access to the remaining attachments.
CAUTIONWhile lowering the table, occasionally stop to make sure no hoses, harnesses, or other components are caught or tangled. Also pay extra attention to the HV battery aero shield mounting tabs.
-
Release the remaining attachments to the drive unit:
-
Carefully lower the powertrain table.
CAUTIONWhile raising the vehicle, have an assistant monitor the underside of the vehicle. Ensure that no components are still connected and that there is sufficient clearance so that no components are damaged.
- Move the powertrain table with subframe away from the vehicle.
Install
-
Pull on the inner halfshaft cup to confirm that the LH and RH rear drive unit halfshafts are fully seated on the rear drive unit, and that the circlip is locked into place.
NoteIf the halfshaft detaches from the rear drive unit, then reinstall the halfshaft paying attention to the following:
- Take care not to damage or displace the oil seals.
- Make sure that the opening of the snap rings are facing towards the bottom of the drive unit.
- Carefully push the halfshaft into the drive unit until there is an audible "click" from the halfshaft stub contacting the pinion shaft.
- There will be a slight pulling sensation on the halfshaft as the halfshaft circlip locks into place.
- Pull on the inner halfshaft cup to confirm that the circlip is locked into place.
-
Drive Units built before October 2014 only: Make sure that no harnesses or cable ties press into the acoustic padding upon reinstallation. Refer to TN-14-40-002, Noise Path for Motor Hum, for more information.
- Move the powertrain table with subframe to under the vehicle.
-
Carefully raise the powertrain table.
CAUTIONWhile raising the table, have an assistant monitor the underside of the vehicle. Make sure that there is sufficient clearance so that no components are damaged.
-
Install the remaining attachments to the drive unit:
-
Carefully raise the powertrain table so that the rear subframe is up against the body.
CAUTIONWhile raising the table, occasionally stop to make sure no hoses, harnesses, or other components are caught or crushed. Also pay extra attention to the HV battery aero shield mounting tabs.
-
Install and hand-tighten the bolts (x4) that secure the rear subframe to the body (torque 140 Nm).
-
Use a crowbar to shimmy the rear subframe with respect to the body, so that the subframe mounting bolts are centered in the tracings, and the witness marks where the subframe contacts the body align.
NoteIt might be necessary to align one corner and tighten the bolt, align the opposite corner and tighten the bolt, and so on in a criss-cross pattern.
- Torque the bolts (x4) that secure the rear subframe to the body (torque 140 Nm).
- Lower the powertrain table and move it out from under the vehicle.
- If the drive unit was removed, refill the gearbox fluid. See Gearbox Fluid - Large Rear Drive Unit (Remove and Replace).
-
Install the coolant hoses to the LH and RH sides of the drive unit.
-
Fasten the clips that secure the HV cables:
- Install 2 new fasteners to secure the HV cables in the rear drive unit (torque 9 Nm).
- Install new O-rings (1003784-00-A or later) on the drive inverter cover and apply Silicone Lubricant (1010251-00-A) on both before installing the cover. Insert the cover at an angle to prevent damage to the O-rings. Once the left (B+) O-ring is seated, rotate the cover into position.
-
Connect the subframe harnesses to the body harness.
- Vehicles built through September 2014: 4 connectors at the back of the rear subframe
- Vehicles built after September 2014: 3 connectors above the RH side of the rear undershield
-
If equipped, install the rear skid plate to the rear subframe, and then install the screws (x2) that secure the skid plate to the subframe (torque 10 Nm).
-
Install the subframe shear plates to the subframe, fasten the clips (x2), and then install the nut (torque 35 Nm) and screws (x3) (torque 6 Nm) that secure each shear plate to the subframe.
-
On both sides of the vehicle,
install the nuts (x3) that attach the mid aeroshield reinforcement.
NoteNuts 10mm, torque 6 Nm.
- Install the mid aero shield. See Panel - Aero Shield - Mid (Remove and Replace).
-
Connect the electrical harnesses to the LH and RH parking brake connectors and then fasten the red locking tabs to secure the connectors.
- Install the plastic park brake connector covers.
-
On both sides of the vehicle, install the rear brake calipers to the rear knuckles, and then install the bolts (x2) that secure each caliper to each knuckle (torque 120 Nm).
CAUTIONTo avoid damage to the brake line, the brake caliper must be supported at all times.
-
On both sides of the vehicle, install and hand-tighten the nut that secures the rear shock absorber to the rear knuckle.
- Remove the bolt that attaches the LH rear brake rotor to the hub.
-
Install the hub jack adapter onto the LH rear hub and hand-tighten the lug nuts.
-
Use an underhoist stand to support the hub jack adapter.
-
Measure the distance between
the top of the upper fore link to the bolt on the frame rail to make sure that
the rear suspension is set to ride height.
NoteDistance should be 85 mm +/- 5 mm.
- Tighten the bolt and nut that attach the LH rear shock absorber to the LH rear knuckle (torque 140 Nm), and then mark the bolt and nut with a paint pen.
- Remove the underhoist stand from underneath the LH rear suspension.
- Remove the lug nuts that attach the hub jack adapter, and then remove the hub jack adapter from the hub.
- Install the bolt that attaches the LH rear brake rotor to the hub.
- Repeat step 25 through 32 for the RH side of the vehicle.
- Install the rear wheels. See Wheel Assembly (Remove and Install).
- Connect 12V power. See Disconnect 12V Power.
-
Perform a coolant air purge
and top off the coolant.
- Remove the vehicle from the 2-post lift.
- Refer to the Alignment Requirement tables to determine whether an EPAS alignment check (EC) or four wheel alignment check (AC) is necessary. If performed, add the alignment check/adjust as a separate activity. See Alignment Requirement - Suspension.