How to Replace a Gm Tcc Lockup Solenoid
Replacing a General Motors Torque Converter Clutch solenoid.
The torque converter clutch solenoid is a hydraulic control valve which is used to control the torque converter clutch. Introduced in the early 1980’s there have been many different solenoid designs used in virtually all the GM automatics both front and rear wheel drive for the past 30 years.
Often when the solenoid goes bad it gets plugged, or stuck in the closed position. This will cause the torque converter clutch to stay engaged, or locked up, when it should be released. This will cause the engine to shutter, and often stall at a stop. This may also be accompanied by a check engine light.
The degree of difficulty in replacing the solenoid depends upon the particular transmission model you are working on. This article will address each model, the procedures involved, and tips and precautions.
Before you begin you will need the following: Transmission pan gasket, replacement transmission filter, replacement torque converter solenoid, necessary tools and enough replacement transmission fluid to refill the transmission when you are done with the job.These items are available at most auto parts stores. My personal recommendation for the solenoid itself is the Rostra brand. The Rostra brand is specifically designed for the aftermarket replacement industry and offers features and benefits to make installation quick and easy.GM Rear wheel drive units 700R4, 2004R, 4L60:With a cool vehicle, begin by removing the transmission oil pan. It is a good idea to keep 2 bolts inserted into diagonally opposite corners, and to gradually remove them to avoid spillage of the transmission fluid. The pan will contain several quarts of transmission fluid, so have an adequately sized catch pan.
Usually the old pan gasket will stick to the oil pan, this must be completely removed. Any remnants of gasket on the transmission case need to be cleanly removed as well. Use a gasket scraper. Now is a good time to clean the inside of the oil pan of the metallic debris and contamination stuck on the pan magnet. Once most of the fluid has drained from the transmission case, you can remove the old filter by pulling it downward. Be sure the seal on the filter neck comes out with the filter, if not reach into the bore and remove the seal.
Under the filter, near the front of the transmission, you will find the solenoid. Remove the two mounting bolts that hold the solenoid to the case. Follow your replacement solenoid wiring instructions, pre lube the solenoid o-ring seal, install the solenoid, and attach the mounting bolts. Install the new filter, pan gasket, and oil pan. Refill transmission to proper level and road test.
GM RWD Units 4L60E, 4L65E, 4L70EThe directions are much the same as those listed above; however, these transmission models have multiple solenoids. The torque converter solenoid is part of the entire internal transmission wiring harness. Often it is best to replace the entire harness, but there are torque converter solenoids available which can be spliced into the existing harness. In either event, removing the old harness is fairly easy. Remove the mounting bolts holding the plastic track to the valve body, Unplug the mating connectors from the remaining solenoids, and remove the two mounting bolts to remove the old solenoid,. Replace in the reverse order. If replacing the entire harness, use an oversized socket to compress the locking tabs of the plastic through case connector, then push the connector inwards to remove it. Always pre lube all O-ring seals. Reinstall filter gasket and pan.
GM RWD 4L80E:Pan and filter removal is the same as above. The torque converter solenoid is a small round can type solenoid which fits into a bore in the valve body, You must remove the electrical connector and the solenoid retaining clip to release the solenoid. Reinstall in the reverse order.
GM FWD Units TH-125, 4T60E:These solenoids are located under the transmission side pan. You will have to remove items such as the battery tray, air snorkel, etc to gain access to the pan mounting bolts. With a bit of creative maneuvering the side pan can be removed to expose the valve body. The torque converter solenoid is held in place by either 1 or 2 bolts. Remove the bolts, remove the solenoid, and install the replacement solenoid valve. Follow the wiring instructions that came with your replacement solenoid, and re-assemble in reverse order. Note that the filter is located under the lower, bottom pan of the transmission, this needs to be replaced at the time of the solenoid change as well.
GM FWD 4T40E, 4T65E:Unless you are an experienced mechanic, with the proper tools and transmission support equipment, replacing the torque converter solenoid should be left to the professional. The vehicle sub frame, suspension, and drive axle often need to be removed to gain proper access.
