For 1990-2009 cars

# INFO ON ALUMINUM RETAINING NUT AND A/C JOINT SEAL GASKETS

#### SUBJECT: INFORMATION ON ALUMINUM RETAINING NUTS AND A/C JOINT SEAL GASKETS

#### VEHICLES AFFECTED: 1992 "C AND H" MODELS PONTIAC BONNEVILLE OLDSMOBILE EIGHTY EIGHT, NINETY EIGHT BUICK LE SABRE, PARK AVENUE CADILLAC DEVILLE, FLEETWOOD

SEAL GASKETS AND ALUMINUM NUTS

Some 1992 C and H models utilize new aluminum retaining nuts to improve torque retention and corrosion resistance along with additional compression seal gaskets for added seal reliability in the event of missing or damaged dual 'O' rings.

ALUMINUM RETAINING NUTS

The aluminum retaining nuts are distinguished by color (silver) and require higher torque 35 N.m (25 lb.ft.) for correct gasket compression. Earlier steel nuts are gold and are torqued to 25 N.m (18 lb.ft.).

SEAL GASKETS

Seal gaskets are thin flat washers with .005 inches of rubber on each flat side. They create a compressive face seal on the A/C lines which requires the aluminum nuts and higher torque. The aluminum nuts maintain compressive joint load over time better than earlier steel nuts. Seal gaskets are reusable when an A/C joint is serviced providing they are not damaged, bent, or cut.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.