Contents Wiring diagrams Section: Frames, Subframes & Crossmembers All sections

Frame and Underbody: Removal & Installation GMC Yukon III

Frames, Subframes & Crossmembers 26 illustrations ~872 words

Removal Procedure

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  2. Remove the mounting bolts for the oil pan skid plate.
  3. Remove the oil pan skid plate.
  4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  5. Remove the mounting bolts for the oil pan skid plate.
  6. Remove the oil pan skid plate.

Installation Procedure

  1. Position the oil skid plate on the frame.
  2. Install the oil skid plate mounting bolts and tighten to 28 N.m (21 lb ft).
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  2. Remove the mounting bolts for the oil pan skid plate.
  3. Remove the oil pan skid plate.
  1. Position the oil pan skid plate on the frame.
  2. Install the oil skid plate mounting bolts and tighten to 28 N.m (21 lb ft).
  3. Lower the vehicle.

Scheme 2

Scheme 2: Engine Shield Replacement
CalloutComponent Name
Preliminary Procedure: Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Engine Shield Bolt (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 20 N.m (15 lb ft)
2Engine Shield
CAUTION
Refer to Fastener Caution .

Scheme 3

Scheme 3: Electronic Brake Control Module Splash Shield Replacement
CalloutComponent Name
Preliminary Procedures: Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Electronic Brake Control Module Splash Shield Retainer (Qty: 2)
2Electronic Brake Control Module Splash Shield Bolt (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 20 N.m (15 lb ft)
3Electronic Brake Control Module Splash Shield
CAUTION
Refer to Fastener Caution .

Scheme 4

Scheme 4: Steering Linkage Shield Replacement
CalloutComponent Name
Preliminary Procedure: Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
1Steering Linkage Shield Bolt (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 20 N.m (15 lb ft)
2Steering Linkage Shield
CAUTION
Refer to Fastener Caution .

Scheme 5

Scheme 5: Drivetrain and Front Suspension Frame Front Crossmember Replacement (2WD 2500HD, 3500)
CalloutComponent Name
Preliminary Procedures Raise the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the oil pan skid plate. Refer to Oil Pan Skid Plate Replacement (2500/3500 with RPO NZZ) or Oil Pan Skid Plate Replacement (1500 with RPO NZZ) .
1Engine Front Crossmember Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 70 N.m (52 lb ft) plus 110 degrees
2Engine Front Crossmember Bolt (Qty: 2) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
3Engine Front Crossmember Nut (Qty: 2) Tighten: 70 N.m (52 lb ft) plus 110 degrees
4Engine Front Crossmember Bolt (Qty: 2) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
5Lower Control Arm Crossmember
CAUTION
Refer to Fastener Caution .

Scheme 6

Scheme 6: Drivetrain and Front Suspension Frame Front Crossmember Replacement (1500, 2500 LD)
CalloutComponent Name
Preliminary Procedure: Remove the oil pan skid plate. Refer to Oil Pan Skid Plate Replacement (2500/3500 with RPO NZZ) or Oil Pan Skid Plate Replacement (1500 with RPO NZZ) .
1Engine Front Crossmember Nut (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 105 N.m (77 lb ft)
2Engine Front Crossmember Bolt (Qty: 4) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
3Lower Control Arm Crossmember
CAUTION
Refer to Fastener Caution .

Scheme 7

Scheme 7: Transmission Support Crossmember Replacement (4WD 2500 Series)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Support the transmission with a transmission jack.
1Transmission Mount to Crossmember Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 50 N.m (37 lb ft)
2Transmission Crossmember Nut (Qty: 4) Tighten: 97 N.m (70 lb ft)
3Transmission Crossmember Bolt (Qty: 4) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
4Transmission Crossmember
CAUTION
Refer to Fastener Caution .

Scheme 8

Scheme 8: Transmission Support Crossmember Replacement (2WD 2500 Series)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Support the transmission with a transmission jack.
1Transmission Mount to Crossmember Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 50 N.m (37 lb ft)
2Transmission Crossmember Nut (Qty: 4) Tighten: 97 N.m (70 lb ft)
3Transmission Crossmember Bolt (Qty: 4) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
4Transmission Crossmember
CAUTION
Refer to Fastener Caution .

Scheme 9

Scheme 9: Transmission Support Crossmember Replacement (2WD 1500 Series)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Support the transmission with a transmission jack.
1Transmission Mount to Crossmember Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 50 N.m (37 lb ft)
2Transmission Crossmember Nut (Qty: 4) Tighten: 97 N.m (70 lb ft)
3Transmission Crossmember Bolt (Qty: 4) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
4Transmission Crossmember
CAUTION
Refer to Fastener Caution .

Scheme 10

Scheme 10: Transmission Support Crossmember Replacement (4WD 1500 Series)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Support the transmission with a transmission jack.
1Transmission Mount to Crossmember Nut (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 50 N.m (37 lb ft)
2Transmission Crossmember Nut (Qty: 4) Tighten: 95 N.m (70 lb ft)
3Transmission Crossmember Bolt (Qty: 4) Procedure Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
4Transmission Crossmember
CAUTION
Refer to Fastener Caution .
  1. Remove the master cylinder. Perform the following steps: Remove the nuts retaining the master cylinder to the brake booster. Remove the master cylinder from the brake booster. Secure the cylinder away from the booster.
  2. Raise the vehicle on the hoist. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  3. Remove the park brake equalizer intermediate cable. Perform the following steps: Remove the nut from the park brake equalizer intermediate cable. Remove the intermediate cable from the equalizer. Depress the retaining tabs that secure the park brake cable to the frame. Pull slightly on the cable from the mounting area in order to provide slack for body movement without binding the cable.
  4. Remove the body mount bolts.
  5. Properly support the body in the area that the mounts will be replaced.
  6. Lower the chassis accordingly in order to remove the cushions (1) as necessary.
  1. Install the cushions (1) as necessary and raise the chassis accordingly.
  2. Perform the following procedure before installing the bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
  3. Install the body mount bolts and tighten to 60 N.m (44 lb ft) plus 200 degrees.
  4. Install the park brake equalizer intermediate cable. Perform the following steps: Pull rearward on the park brake cable to the original position. Secure the cable retaining tabs to the frame. Install the intermediate cable end to the equalizer. Install the nut to the threaded end of the intermediate cable and tighten to 4 N.m (31 lb in).
  5. Lower the vehicle.
  6. Install the master cylinder. Perform the following steps: Mount the master cylinder to the brake booster. Install the master cylinder mounting nuts and tighten to 36 N.m (27 lb ft).
  1. Remove the master cylinder. Perform the following steps: Remove the nuts retaining the master cylinder to the brake booster. Remove the master cylinder from the brake booster. Secure the cylinder away from the booster.
  2. Raise the vehicle on the hoist. Refer to «Lifting and Jacking the Vehicle»(ref-364496-S07186948972010063000000) .
  3. Remove the park brake equalizer intermediate cable. Perform the following steps: Remove the nut from the park brake equalizer intermediate cable. Remove the intermediate cable from the equalizer. Depress the retaining tabs that secure the park brake cable to the frame. Pull slightly on the cable from the mounting area in order to provide slack for body movement without binding the cable.
  4. Remove the body mount bolts.
  5. Properly support the body in the area that the mounts will be replaced.
  6. Lower the chassis accordingly in order to remove the cushions (1), as necessary.
  1. Install the cushions (1) as necessary and raise the chassis accordingly.
  2. Perform the following procedure before installing the bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488).
  3. Install the body mount bolts and tighten to 60 N.m (44 lb ft) plus 200 degrees.
  4. Install the park brake equalizer intermediate cable. Perform the following steps: Pull rearward on the park brake cable to the original position. Secure the cable retaining tabs to the frame. Install the intermediate cable end to the equalizer. Install the nut to the threaded end of the intermediate cable and tighten to 4 N.m (31 lb in).
  5. Lower the vehicle.
  6. Install the master cylinder. Perform the following steps: Mount the master cylinder to the brake booster. Install the master cylinder mounting nuts and tighten to 36 N.m (27 lb ft).

Scheme 11

Scheme 11: Front Wheelhouse Liner Replacement - Right Side
CalloutComponent Name
Preliminary Procedure: Remove the appropriate tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Right Side Front Wheelhouse Liner Screws (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2Right Side Front Wheelhouse Liner Plastic Retainers (Qty: 12)
3Right Side Front Wheelhouse Liner Tip: Before attempting to remove the wheelhouse liner remove any plastic retainers and/or bolts passing through or attached to the right side front wheelhouse liner.
CAUTION
Refer to Fastener Caution .

Front Wheelhouse Liner Replacement - Left Side

CalloutComponent Name
Preliminary Procedure: Remove the appropriate tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Left Side Front Wheelhouse Liner Screws (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2Left Side Front Wheelhouse Liner Plastic Retainers (Qty: 11)
3Left Side Front Wheelhouse Liner Tip: Before attempting to remove the wheelhouse liner remove any plastic retainers and/or bolts passing through or attached to the left side front wheelhouse liner.
CAUTION
Refer to Fastener Caution .

Scheme 12

Scheme 12: Rear Wheelhouse Panel Extension Replacement (RPO QST Only)
CalloutComponent Name
1Rear Wheelhouse Panel Extension Screw (Qty: 7) CAUTION: Refer to Fastener Caution . Tighten: 2.5 N.m (22 lb in)
2Rear Wheelhouse Panel Extension Procedure Position and hold the rear wheelhouse extension to the wheelhouse. Secure the top three screws first. Secure the front and rear wheelhouse screws last.
CAUTION
Refer to Fastener Caution .

Scheme 13

Scheme 13: Rear Wheelhouse Panel Liner Replacement (RPO HP2)
CalloutComponent Name
Preliminary Procedure: Remove the appropriate tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Rear Wheelhouse Panel Liner Screw (Qty: 6) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2Rear Wheelhouse Panel Liner Plastic Retainer (Qty: 4)
3Rear Wheelhouse Panel Liner Tip: Before attempting to remove the wheelhouse liner remove any plastic retainers and/or bolts passing through or attached to the rear wheelhouse panel liner.
CAUTION
Refer to Fastener Caution .

Scheme 14

Scheme 14: Rear Wheelhouse Panel Liner Replacement (RPO X88 Chevrolet, RPO O88 GMC)
CalloutComponent Name
Preliminary Procedure: Remove the appropriate tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Rear Wheelhouse Liner Retainer (Qty: 3)
2Rear Wheelhouse Liner Screw (Qty: 7) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
3Rear Wheelhouse Liner Tip: Before attempting to remove the wheelhouse liner remove any plastic retainers and/or bolts passing through or attached to the wheelhouse liner.
CAUTION
Refer to Fastener Caution .

Scheme 15

Scheme 15: Front Wheelhouse Panel Front Extension Replacement (RPO QST Only)
CalloutComponent Name
1Front Wheelhouse Liner Screw CAUTION: Refer to Fastener Caution . Tighten: 2.5 N.m (22 lb in)
2Push Pin Retainer (Qty: 4) Tip: Install the retainers prior to installing the screws.
3Front Wheelhouse Liner Rear Screw (Qty: 2) Tighten: 2.5 N.m (22 lb in)
4Front Wheelhouse Panel Front Extension
CAUTION
Refer to Fastener Caution .

Scheme 16

Scheme 16: Wheelhouse Panel Replacement - Right Side (HP2)
CalloutComponent Name
Preliminary Procedure: Remove the appropriate tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Front Wheelhouse Liner Bolt/Screw (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2Front Wheelhouse Liner Plastic Retainer (Qty: 13)
3Front Wheelhouse Liner Tip: Disconnect any electrical connectors.
CAUTION
Refer to Fastener Caution .

Scheme 17

Scheme 17: Wheelhouse Panel Replacement - Left Side (HP2)
CalloutComponent Name
Preliminary Procedure: Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Front Wheelhouse Liner Bolt/Screw (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 2 N.m (18 lb in)
2Front Wheelhouse Liner Left Side Push-Pin (Qty: 10)
3Front Wheelhouse Liner
CAUTION
Refer to Fastener Caution .

Scheme 18

Scheme 18: Assist Step Replacement (Z71)
CalloutComponent Name
1Assist Step Bolt (Qty: 9) CAUTION: Refer to Fastener Caution . Tighten: 23 N.m (17 lb ft) Tip: Suburban shown, other models similar. Assemble the assist step completely before installing to the vehicle. Torque bolts in the sequence shown.
2Assist Step Assembly
CAUTION
Refer to Fastener Caution .

Scheme 19

Scheme 19: Assist Step Replacement (Power BRS)
CalloutComponent Name
Preliminary Procedures Deploy the power assist step. Mark the location of the front T-slotted bracket and measure to the front of the assist step with a grease pencil and tape measure. Transfer the measurement to the new assist step with the grease pencil and tape measure. Mark the location of the rear T-slotted bracket and measure to the rear of the assist step with a grease pencil and tape measure. Transfer the measurement to the new assist step with the grease pencil and tape measure.
1Power Assist Step Bolt (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten: 12 N.m (106 lb in)
2Power Assist Step IMPORTANT: It is essential to make the measurements in the preliminary procedures or the power assist steps may not be aligned to the body properly. Tip: Transfer any parts as needed.
CAUTION
Refer to Fastener Caution .
IMPORTANT
It is essential to make the measurements in the preliminary procedures or the power assist steps may not be aligned to the body properly.

Scheme 20

Scheme 20: Assist Step Replacement (Chevrolet HP2)
CalloutComponent Name
Preliminary Procedure: Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Assist Step Extension
2Assist Step Extension Bolt CAUTION: Refer to Fastener Caution . Tighten: 18 N.m (13 lb ft)
3Assist Step Assembly
4Assist Step Assembly Bracket Bolt (Qty: 8) Tighten: 18 N.m (13 lb ft) Tip: Secure the forward and rearward bolts first after the assist step has been installed.
5Assist Step Bracket Body Bolt (Qty: 4) Tighten: 18 N.m (13 lb ft)
CAUTION
Refer to Fastener Caution .

Scheme 21

Scheme 21: Assist Step Replacement (GMC Denali XL)
CalloutComponent Name
1Assist Step Front (RH) Extension Bolt with Compression Limiter CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Assist Step Support Bolt (Qty: 4) Tighten: 6 N.m (53 lb in)
3Assist Step Support Bracket Bolt (Qty: 4) Tighten: 6 N.m (53 lb in)
4Assist Step Front (RH) Extension Tip: Position the extension to the assist step prior to securing the nuts and bolts.
5Assist Step Bracket (Qty: 4) Tip: Assemble all of the brackets to the assist step prior to hanging the assist step brackets to the lower rocker panel studs.
6Assist (RH) Step Tip: Right hand assist step shown, left hand side similar.
7Rocker Panel Stud Nut (Qty: 4) Tighten: 6 N.m (53 lb in)
CAUTION
Refer to Fastener Caution .

Scheme 22

Scheme 22: Assist Step Pad Replacement (Power BRS)
CalloutComponent Name
1Power Assist Step Pad Procedure Deploy the power assist step. Use a trim panel removal tool to help ease the release of the clips holding the pad in.

Scheme 23

Scheme 23: Assist Step Finish Cover Replacement (Power BRS)
CalloutComponent Name
Preliminary Procedures Deploy the power assist step. Remove the power assist step pad. Refer to Assist Step Pad Replacement (Power BRS) .
1Power Assist Step Finish Cover Screws (Qty: 10) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Power Assist Step Finish Cover
CAUTION
Refer to Fastener Caution .

Scheme 24

Scheme 24: Assist Step Front Bracket Replacement
CalloutComponent Name
Preliminary Procedures Deploy and support the power assist step. Use a grease pencil to outline the location of the power assist step front bracket location on the power assist step. Remove the power assist front bracket to power assist step bolts. Refer to Assist Step Replacement (Z71) or Assist Step Replacement (Power BRS) or Assist Step Replacement (Chevrolet HP2) or Assist Step Replacement (GMC Denali XL) Remove the power assist step motor. Refer to Assist Step Motor Replacement (Power BRS) .
1Power Assist Step Front Bracket Bolts (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Power Assist Step Front Bracket Nuts (Qty: 3) Tighten: 10 N.m (89 lb in)
3Power Assist Step Front Bracket
CAUTION
Refer to Fastener Caution .

Scheme 25

Scheme 25: Assist Step Rear Bracket Replacement
CalloutComponent Name
Preliminary Procedures Deploy and support the power assist step. Use a grease pencil to outline the location of the power assist step rear bracket location on the power assist step. Remove the power assist rear bracket to power assist step bolts. Refer to Assist Step Replacement (Z71) or Assist Step Replacement (Power BRS) or Assist Step Replacement (Chevrolet HP2) or Assist Step Replacement (GMC Denali XL)
1Power Assist Step Rear Bracket Bolts (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Power Assist Step Rear Bracket Nuts (Qty: 3) Tighten: 10 N.m (89 lb in)
3Power Assist Step Rear Bracket
CAUTION
Refer to Fastener Caution .

Scheme 26

Scheme 26: Assist Step Controller Replacement (Power BRS)
CalloutComponent Name
1Power Assist Step Controller Bolt (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten: 6 N.m (53 lb in)
2Power Assist Step Controller Procedure Disconnect any electrical connectors. Reprogram the new controller if necessary. Refer to Control Module References .
CAUTION
Refer to Fastener Caution .

Scheme 27

Scheme 27: Assist Step Motor Replacement (Power BRS)
CalloutComponent Name
Preliminary Procedures Deploy the power assist step. Remove the two motor cover bolts. Disconnect any electrical connectors. Remove the three motor bolts. Remove the wedge bolt and wedge. Loosen the link nuts, but Do Not Remove. Pull the motor inboard and rearward in order to clear the weld joint. Remove the motor.
1Assist Step Motor Wedge Bolt CAUTION: Refer to Fastener Caution . Tighten: 8 N.m (71 lb in)
2Assist Step Motor Wedge
3Assist Step Motor Bolt (Qty: 3) Tighten: 12 N.m (9 lb ft)
4Assist Step Motor Procedure Pull the motor inboard and wiggle forward to position and install the motor in place. Install the two link bolts. Tighten the three link nuts. Install the motor bolts. Install the wedge and wedge bolt. The wedge shape should point upward and outward to position correctly. Install the cover and two motor cover bolts. Tip: Make sure the flat on the motor is parallel to the floor before installing. All new motors should be shipped with motor flat in the correct position. As the motor is installed shake the board up and down gently to make sure the wedge and flat seat together correctly or unwanted noise could result. Once the installation of the new motor is completed the assist step must be cycled once for the module to learn the positioning.
CAUTION
Refer to Fastener Caution .
  1. Disconnect the trailer wiring harness.
  2. Remove the hitch platform bolts from the frame rails and the rear bumper.
  3. Remove the hitch platform from the vehicle.
  1. Position the hitch platform to the vehicle.
  2. Install the platform hitch bolts to the frame rails and the rear bumper. Tighten the trailer hitch-to-frame bolts to 113 N.m (83 lb ft). Tighten the trailer hitch-to-bumper bolts to 100 N.m (74 lb ft).
  3. Connect the trailer wiring harness.