DOOR LOCK CYLINDERS RECOMMENDED LUBRICATION

SUBJECT: DOOR LOCK CYLINDERS - RECOMMENDED LUBRICATION

MODELS/MAKE ALL 1993 AND PREVIOUS MODEL CARS AND TRUCKS

This bulletin cancels and supersedes the Service Guild Article "Door Lock Cylinders - All Models" published September 1990.

Customer comments of binding/sticking door lock cylinders, or keys that are hard to insert or extract may be corrected in many cases by applying the proper lubrication.

The recommended materials for lubricating these components are (in order of preference):

0 GM # 12345120 Multi purpose lubricant (9 oz. spray) or # 12345121 (12 oz.).

0 5 W 30 Synthetic Motor Oil

Penetrating oil type lubricants (such as GM # 1052949 or 1052950, WD-40 lubricants) ARE NOT RECOMMENDED because they wash out the original lubrication and eventually evaporate, leaving little or no lubricating material. However, if these type materials are used to "unfreeze" or loosen lock cylinder components, refer to steps 2 through 4 listed below for the proper methods of lubricating.

Important: Do not replace the door lock cylinders until after the lubricating materials have been used and the cylinder remains frozen/bound.

If door lock cylinders require replacement for any reason, apply a coating of GM # 12345120 Multi purpose Lubricant to the inside of the lock case and the cylinder key way prior to assembling and installing the cylinder.

Parts are currently available from GMSPO.

Frozen cylinders due to cold weather may be repaired using the following procedure:

1. Apply heat to the cylinder area with a heat gun while being careful not to damage the painted surfaces. 2. Hold the shutter door open with a paper clip (or similar item) and force air into the cylinder using compressed air and a blow gun attachment. 3. While holding the shutter door open, inject a small amount of lubricant (see above recommendations) into the cylinder. 4. Work the key into the cylinder several times and wipe any excess lubrication residue from the key.

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.