How to Replace a Flex Plate

by Don Bowman

A flex-plate is used in vehicles with an automatic transmission. It is directly attached to the rear of the engine on the crankshaft. The flex-plate has a ring gear surrounding the outside circumference. The ring gear is used in conjunction with the starter to start the engine. The flex-plate supplies the power to the transmission through the direct connection of the torque converter.

Disconnect the negative battery cable using a wrench. Remove all electrical connections attached to the transmission by unplugging them.

Remove all bolts in the bell housing that are located on the top of the bell housing under the hood. Use the 3/8-inch drive ratchet and the appropriate sockets.

Remove the starter by removing the two bolts that extend through the bell housing into the starter.

Disconnect the gearshift linkage on the top of the transmission case by prying up on the cable to the shift linkage end with a common screwdriver. Use the screwdriver to pry the shift cable out of its retainer so it is free of the transmission.

Remove the upper transmission mount. Use the 3/8-inch ratchet and appropriate socket. The transmission will not fall since it is still bolted on the bottom. Remove the transmission cooler lines using the common screwdriver.

Survey the top side of the transmission for anything that is still bolted or hooked to the transmission that will cause problems with the removal of the transmission. Attach the engine support bar to the fender-wells. Attach the chains to the engine. Allow four inches of slack so the transmission can drop down by this amount.

Raise and support the vehicle on all four corners with jack stands. Remove the front wheels using the half-inch air gun and the appropriate socket.

Remove the brake caliper by extracting the two bolts holding the caliper to the mounting bracket using a 3/8-inch drive socket and ratchet. Hang the caliper up with a clothes hanger or some other device so it does not hang by its hose.

Unbolt the tie rod where it attaches to the spindle. Remove the cotter pin from the tie rod stud with the wire cuttters. Unscrew the nut holding the tie rod stud to the spindle. Insert the ball joint and tie rod remover tool between the tie rod end and the spindle. Hit the tool with a hammer until the tie rod comes loose. Lift the tie rod out of the spindle.

Unscrew the large CV shaft nut on the end of the drive shaft. The nut is located in the center of the rotor. Unscrew the two large bolts and nuts connecting the base of the strut to the spindle. Pull the spindle to separate from the strut.

Push the axle through the hub bearing to separate the axle from the spindle. Remove the CV drive axle from the transmission by using the pry bar to pry the axle out of the transmission. Do the same for the other side.

Unscrew the four bolts on the lower torque converter cover to remove the torque converter cover. Unscrew the bolts holding the torque converter to the flex-plate through the access hole created by removing the plate.

Move the floor jack to a spot under the transmission pan and lift the transmission just slightly to relieve the weight on the mounts. Unscrew the bolts through the front and rear transmission mounts. Unscrew all remaining bolts in the bell housing.

Remove the speed sensor located in the top of the differential housing by the firewall. Use a 10-mm wrench to extract the bolt holding it in and pull the sensor out of the housing.

Separate the transmission from the engine using a common screwdriver to pry them apart at the bell housing. Lower the transmission and remove from under the vehicle.

Remove the center bolts in the flex-plate using the half-inch drive air gun and the appropriate socket. Replace all parts in reverse order of removal.

Items you will need

About the Author

Don Bowman has been writing for various websites and several online magazines since 2008. He has owned an auto service facility since 1982 and has over 45 years of technical experience as a master ASE tech. Bowman has a business degree from Pennsylvania State University and was an officer in the U.S. Army (aircraft maintenance officer, pilot, six Air Medal awards, two tours Vietnam).

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