GM Service Manual Online
For 1990-2009 cars only

THM TRANS OIL LEAKS USE TRACING POWDER/FIND LEAK

VEHICLES AFFECTED: VEHICLES EQUIPPED WITH THM 125-C, 200-C, 325-4L, AND 200-4R TRANSMISSIONS WHEN ANY THM TRANSMISSION OIL LEAK IS DETECTED, IT IS VERY IMPORTANT THAT THEY ARE DIAGNOSED PROPERLY, AS TO LOCATION AND TYPE OF LEAK. THE FOLLOWING PROCEDURE WILL HELP IN DIAGNOSING THE TYPE AND LOCATION OF THE LEAK AND WILL SUGGEST A CORRECTION METHOD. DIAGNOSIS PROCEDURE: (ALL MODELS) THE FOLLOWING PROCEDURE CAN BE PERFORMED ON CAR. 1. CLEAN ALL RESIDUAL OIL FROM THE TRANSMISSION, CONCENTRATING ON THE TRANS. OIL PAN TO CASE MATING AREA (ALL MODELS), T.V. CABLE CONNECTOR (ALL MODELS), TRANS OIL PAN TO SPROCKET COVER INTERFACE AREA (325-4L MODEL), FINAL DRIVE TO CASE CONNECTION (325-4L MODEL), AND VALVE BODY COVER TO TRANS. OIL PAN INTERFACE AREA (125C MODEL) (ENGINE SHAMPOO P/N 992878 OR EQUIVALENT IS RECOMMENDED). 2. DUST THE ENTIRE TRANSMISSION WITH A WHITE POWDER. 3. AFTER NORMAL OPERATING TEMPERATURE 76 DEGREES C (170 DEGREES F) HAS BEEN OBTAINED, LET THE TRANSMISSION STAND FOR AT LEAST 30 MINUTES. 4. INSPECT THE TRANSMISSION FOR LEAKAGE BY FOLLOWING RED OIL TRACES LEFT IN THE POWDER. (IF RESIDUAL OIL IS LEFT ON THE TRANSMISSION OIL PAN OR SPROCKET COVER, IT WILL NECESSITATE THE CLEANING AND DUSTING PROCEDURE TO BE REPEATED.) 5. ONCE THE LEAK HAS BEEN DIAGNOSED AS TO LOCATION AND TYPE REFER TO THE FOLLOWING REPAIR PROCEDURE.(**SEE BULLETIN**)


Object Number: 84845  Size: FS


Object Number: 86149  Size: FS


Object Number: 85526  Size: FS


Object Number: 86148  Size: FS

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.