GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Transmission 🢒 Automatic Transmission - Allison 🢒 Transmission Fluid Auxiliary Cooler Inlet and Outlet Hose Replacement

Removal Procedure
  1. Open the hood.
  2. Place a drain pan under the transmission oil cooler line.

    3. Object Number: 787959 Size: SH
  3. Unclip and remove the oil cooler line (1) from the retaining bracket (2).
  4. Remove the upper transmission oil cooler (TOC) line from the radiator. Refer to Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection.
  5. Remove the grille. Refer to Grille Replacement.
  6. Close the hood.
  7. Unclip and remove the auxiliary TOC line from the retaining bracket.
  8. Remove the nut from the auxiliary TOC line block fitting.
  9. Remove the auxiliary TOC line from the oil cooler.
  10. Remove the auxiliary TOC line from the vehicle.

Installation Procedure
  1. Install the auxiliary TOC line to the vehicle.
  2. Install new sealing washer.
  3. Install the auxiliary TOC line to the cooler block fitting.

    4. Caution: Refer to Fastener Caution in the Preface section.

  4. Install the nut to the auxiliary TOC line block fitting.

    5. Tighten
    Tighten the nut to 16 N·m (12 lb ft).

  5. Install the auxiliary TOC line to the retaining bracket.

    6. Object Number: 787959 Size: SH
  6. Install the TOC line (1) to the retaining bracket (2).
  7. Open the hood.
  8. Install the grille. Refer to Grille Replacement.
  9. Install the upper TOC line to the radiator. Refer to Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection.
  10. Inspect the transmission fluid level. Refer to Fluid Capacity Specifications.
  11. With the engine running, inspect the oil cooler lines for leaks.