How to Change a Car Flywheel

The car flywheel is a one-piece unit, located between the transmission and engine block. Its purpose is to provide power and energy to the pistons during their downward motion. The flywheel has teeth on the outer edge, that the starter motor uses to turn the motor prior to the engine firing.

You may never have to replace the flywheel, however if the teeth become worn or broken, a new flywheel will need to be installed.

Tools and Materials

  • Car flywheel
  • Automotive lift access, if possible
  • Car jack and jack stands
  • Socket wrench and sockets
  • Flare nut wrench
  • Drip pan
  • Transmission fluid

Step 1 – Preparation

If you have access to an automotive lift, it will make this job much easier. If not, jack up the front of your car and slide 2 jack stands under the car. Set the jack stands high enough to allow you to work underneath comfortably.

Locate the U-bolts, that connect the drive shaft to the transmission housing, and remove them. Set the drip pan under the area and pull the drive shaft away from the transmission. Catch the fluid draining from the transmission with the drip pan.

Next disconnect the shift linkage, transmission cooler hoses and the speedometer. You will need to use the flare-nut wrench to remove the transmission cooler hose connections.

Step 2 – Removing the Transmission

Place your floor jack under the transmission housing and raise the jack until it is securely connected to the transmission.

Remove the bolts securing the torque converter to the flywheel, and remove the bolts holding the transmission to the engine block. After removing the transmission cross member, remove the transmission away from the engine block and slide it out of the way with the floor jack.

Step 3 – Replacing the Flywheel

Remove the bolts securing the car flywheel to the crankshaft. Pull the flywheel off the crankshaft and set it out of the way. Take the new flywheel and push it all the way onto the crankshaft and secure it using the bolts from the old flywheel.

Step 4 – Reinstalling the Transmission

Slide the transmission back into position, and reattach and tighten the torque converter. With the converter fastened, install the bolts into the transmission housing, and secure it against the engine block.

Put the transmission cross member back into position, and secure it back onto the car's frame. Reattach the transmission cooling hoses, the speedometer and shift linkage back into position and tighten their bolts.

Insert the driveshaft back into the transmission housing. Place the rear of the driveshaft against the differential, and reattach the U-bolts to secure the driveshaft assembly.

Replace any transmission fluid that dripped out. The transmission fill tube is located in the engine compartment.

Step 5 – Finishing Steps

Check for any fluid leaks and retighten any bolts or hoses as necessary. Pull the drip pan out from under the car and lower the floor jack off of the transmission housing. Jack the car back up high enough to remove the jack stands and slowly lower the car back to the ground.

Now that changing the car flywheel is complete, be sure to dispose of the old transmission fluid according to local safety codes.