How to Replace a Torque Converter
by Francis Walsh
An automatic transmission uses a torque converter to pass energy from the engine into the transmission. A torque converter is essentially a tub of fluid secured to the engine's flywheel that acts like an adjustable vise when spinning. The converter pushes fluid through tiny compartments inside its tub to create pressure. When the pressure is high enough, the converter passes the spinning energy from the engine into the transmission. You should replace a torque converter that is broken or one that cannot handle the power of an engine. Matching the right torque converter to an engine adds to the life of the transmission and allows the engine to operate at a higher level of performance.
Step 1
Park you car on a flat, clean surface.
Step 2
Jack one end of the vehicle off the ground and support the weight onto two automotive jack stands. Adjust the stand to a height high enough to extract a transmission out from under the vehicle. Set the weight down onto the stands and move to the other end of the vehicle. Lift the vehicle up and lower it onto two more jack stands set at the same height as the others. The vehicle should be level and the lifting jack removed from its lifting position.
Step 3
Go under the vehicle to the end of the drive shaft that connects it to the rear axle. There is a universal joint that holds the two pieces together. The universal joint will stay inside one of the yokes when separated. Two U-bolts secure the universal joint to the rear axle's yoke, and each U-bolt has two nuts. Loosen and remove all four U-bolt nuts and pull the U-bolts free from the yoke.
Step 4
Place the vehicle in neutral so that the drive shaft can be turned. To separate the two yokes, move the universal joint so that one of the free ends will be tipped away from the rear axle. With the universal jointed tipped like this, you can turn the drive shaft and pull the shaft away from the rear axle yoke. Hold the free end of the drive shaft above the rear axle yoke and tap or pull on the drive shaft to separate it from the back of the transmission.
Step 5
Open the hood of the vehicle and locate the transmission fill tube. Follow the length of the tube back toward the transmission to find the bracket or tab that is used to secure it in place. Remove the bolt that goes through the fill tube tab, and pull up on the tube to remove it from the transmission. The tube can be separated from the rubber grommet that lines the fluid fill port on the transmission.
Step 6
Set the car in park. Go under the vehicle to where the torque converter is visible at the front of the transmission. Loosen and remove the bolts that fasten the torque converter to the fly wheel. The torque converter has three or four "feet" that each has a nut and a bolt to remove plus three or four bolts that tighten directly into the converter.
Step 7
Place a floor jack under the transmission pan and raise the arm up to the pan and put some upward pressure on the transmission. This relieves the cross member that helps support the tail of the transmission. Remove the bolts that fasten the transmission to the cross member and the cross member bolts that secure it to vehicle's frame. Use the floor jack to lift the transmission up high enough to remove the cross member from under it.
Step 8
Loosen the transmission's bell housing bolts securing the transmission to the engine. An extension and ratcheting wrench with the correct socket will be able to reach and remove the six or seven bolts that are there. When you pull the transmission away from the motor, the weight is all on the jack. Before you pull it away, it sits on two pins sticking out of the motor. Pull the transmission away from the motor and lower it down so that the jack can be removed and the transmission set on the ground.
Step 9
Pull the old torque converter off the transmission's input shaft. Fill a new torque converter with a quart of transmission fluid and push onto the transmission input shaft. The input shaft and the fluid pump that is located at the front of the transmission have a notched tube that the torque converter's drive collar must mesh with. With the torque converter pressed onto the input shaft, turn the converter one way or the other until the converter meshes with the notch and it seats completely in place. Look down the input shaft to see the notches. Line the converter up with the shaft when you push it on for an easier fit.
Step 10
Reinstall the transmission in reverse order. Fill the transmission with fluid and check the fluid level with the vehicle running. A new torque converter will give a good transmission new life and the vehicle owner a new way of driving with a difference in acceleration and takeoff performance with a new, better matching torque converter.
Tips
- Use tie wraps to secure the torque converter onto the input shaft during removal. The converter can slide off the shaft and damage the transmission if not fastened to the bell housing using tie wraps. Have some rags ready and brake cleaner if the undercarriage of the vehicle is dirty. The drive shaft is easy to separate. Point one of the cup bearings away from the rear axle, then turn the drive shaft and pull the two pieces apart.
Things You'll Need
- Torque converter
- Transmission fluid
- Floor jack
- Tie wraps
- Jack stand
- Open and closed end wrenches: 3/8, 9/16, 7/16, 1/2 inch
- Extension at least 12 inches long
- Ratchet
- Sockets
Warnings
- Working under a vehicle can result in debris and fluid falling into your eyes. Always wear glasses to protect your eyes from an accident that can take your sight.
Writer Bio
Francis Walsh has been working as a freelance writer since 2003. He has contributed to websites such as Shave, Autogeek and Torque & Chromeas, as well as provided content for private clients. Walsh has worked as a performance part-packer and classic car show promoter, now serving as crew chief for Nitrousfitz Racing.
