For 1990-2009 cars

# DIESEL FRONT COVER OIL SEAL INSTALLATION CORRECTION

THE PROCEDURE FOR INSTALLING THE FRONT COVER OIL SEAL ON 1978-1982 V8 DIESEL ENGINES IS INCORRECT IN THE 1978-1982 CHASSIS SERVICE MANUALS. THE FOLLOWING GIVES THE CORRECT INSTALLATION PROCEDURE USING A MODIFIED BT-6405 OR J-25264 TOOL. (1982 TOOL J-29659 WILL NOT WORK ON A V8 DIESEL.) MODIFY TOOL BT-6405 OR J-25264 SEAL INSTALLER BY FILLING .508MM (.020") FROM THE SHADED AREA SHOWN IN FIG. 4. IF THE TOOL IS NOT MODIFIED, THE TOOL WILL CONTACT THE OIL SLINGER PRIOR TO THE SEAL BEING PROPERLY INSTALLED. TO REMOVE THE SEAL, USE THE EXISTING PROCEDURES. AFTER THE SEAL IS REMOVED, USE A TAPERED REAMER OR BEARING SCRAPER TO REMOVE ANY BURRS IN THE FRONT COVER OPENING AND ALSO TO FORM A CHAMFER. THE CHAMFER IS REQUIRED SO THAT THE SEAL CAN BE PRESSED INTO THE FRONT COVER "SQUARE". REMOVING ANY BURRS ELIMINATES THE POSSIBILITY OF OIL LEAKS AROUND THE SEAL'S OUTSIDE DIAMETER. INSTALLATION 1.APPLY 1050026 SEALER OR EQUIVALENT TO OUTSIDE DIAMETER OF SEAL. 2.USING THE MODIFIED SEAL INSTALLER BT-6405 OR J-25264, INSTALL SEAL SQUARELY INTO THE FRONT COVER AS SHOWN IN FIG. 4. MAKE CERTAIN THE SEAL IS INSTALLED FLUSH AND SQUARE WITH THE OPENING IN THE FRONT COVER. 3.INSTALL THE CRANKSHAFT BALANCER - SEE "BALANCER INSTALLATION"

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.