GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 38042 Dual O-Ring Tube Separator

Important: Use only recommended service replacement air conditioning O-rings, even though other O-rings may look similar. Excessive leakage of Refrigerant 134a may occur if the recommended O-rings are not used.

Install new GM-approved service replacement air conditioning O-rings whenever a joint or fitting is disassembled, except when provided on new components.

When replacing O-rings on an air conditioning component or joint connection, carefully identify the fitting design in order to ensure installation of the correct air conditioning service replacement O-ring.


Object Number: 247055  Size: SH

This vehicle uses dual O-ring joints in the system. The dual O-ring design increases the durability of the joint seal by providing a second O-ring seal. The dual O-ring fitting consists of the following components:

    • An aluminum-alloy, externally-threaded fitting, that is brazed or welded to an aluminum tube
    • A free-spinning, plated steel, internally-threaded nut
    • A precision-machined, male-piloted aluminum tube end that accommodates 2 O-rings

Use the following procedures when you service dual O-ring joints:

  1. Completely recover the refrigerant from the system.

  2. Object Number: 247054  Size: SH
  3. Use the J 38042 in order to separate the joint while loosening the female nut.
  4. Important: 

       • Dual O-ring fittings are different in size from the standard A/C fitting O-rings.
       • Dual O-ring fittings require a steel nut torque of 24 N·m (18 lb ft).

  5. Replace the old O-rings with new O-rings when a fitting joint is opened.
  6. Use a nonmetallic tool in order to prevent damage to the seal surface when you remove O-rings.
  7. Do not excessively stretch or twist the replacement O-rings.
  8. Apply a small amount of 525 viscosity A/C oil in order to ease insertion.
  9. Align the ends for pilot-to-bore insertion. Push the ends together completely.

Before installing, verify that both O-rings and fittings are not nicked or deformed. Replace any damaged parts.