For 1990-2009 cars

Install new GM approved service replacement air conditioning (A/C) O-rings whenever a joint or a fitting is installed. The only exception is when the new replacement components provide the O-rings. Unless service replacement O-rings of the specified part numbers are used, excessive leakage of the Refrigerant-134a may occur. Refer to the part number for identification.

Important: Keep polyalkaline glycol (PAG) refrigerant oil off the fitting threads. Long term contact of the oil on the threads may cause future disassembly difficulties.

Coat the A/C O-rings with mineral base 525 viscosity refrigerant oil immediately prior to installation. Slip the O-rings onto the flange pipe in order to assure proper locating and sealing. In order to prevent the possibility of swelling and a reduction in the sealing effectiveness, do not soak the O-rings in the refrigerant oil. Examine the O-rings and the fittings before the installation in order to ensure that the O-rings and the fittings are not nicked or deformed. Replace any nicked or deformed parts in order to prevent refrigerant leakage.