SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 718 (HEATING, VENTILATION & AIR CONDITIONING)REPAIR INSTRUCTIONSO-RING REPLACEMENTINSTALLATION PROCEDURE
1999 GMC Forward Control 5.7 R, Automatic

Installation Procedure

1999 GMC Forward Control 5.7 R, AutomaticSECTION Installation Procedure
WARNING: This page is about a different car, the 2002 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
  1. Remove the cap or tape from the A/C refrigerant hose and the A/C refrigerant component.
  2. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the A/C refrigerant hose and the A/C refrigerant component.
  3. For compression-style fittings, carefully slide the new O-ring seal (1) onto the A/C refrigerant hose until seated.

    Important:  DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the new O-ring seal to enter the refrigerant system.

  4. Lightly coat the new O-ring seal (1) with mineral base 525 viscosity refrigerant oil.
    Fig 1: O-Ring Seal
    G01672609Courtesy of GENERAL MOTORS CORP.
  5. For banjo-style fittings, carefully slide the new O-ring seal (1) onto the A/C refrigerant hose until seated.

    Important:  DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the new O-ring seal to enter the refrigerant system.

  6. Lightly coat the new O-ring seal (1) with mineral base 525 viscosity refrigerant oil.

    Leave a light coating of the refrigerant oil to remain on the A/C refrigerant hose in the area indicated (2) ONLY.

    Fig 2: O-Ring Seal & Location For Light Coating Of Refrigerant Oil
    G01672610Courtesy of GENERAL MOTORS CORP.
  7. Install the A/C refrigerant hose to the A/C refrigerant component.
  8. For compression-style fittings, use a back-up wrench on the A/C refrigerant component (smaller size) fitting (2), then tighten the A/C refrigerant hose (larger size) fitting (1) to specification.
  9. For banjo-style fittings, install the bolt/nut retaining the A/C refrigerant hose to the A/C refrigerant component, then tighten to specification.
  10. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  11. Leak test the fittings of the component using J 39400-A  .
    Fig 3: Installing O-Ring From A/C Refrigerant Hose Fittings
    G01672611Courtesy of GENERAL MOTORS CORP.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.