Mazda Trucks 1972-1986 Repair Guide

Flywheel/Flexplate and Ring Gear


Flexplate is the term for a flywheel mated with an automatic transmission.


The ring gear is replaceable only on engines mated with a manual transmission. Engine with automatic transmissions have ring gears which are welded to the flexplate.

  1. Remove the transmission.
  3. Remove the clutch, if equipped, or torque converter from the flywheel. The flywheel bolts should be loosened a little at a time in a cross pattern to avoid warping the flywheel. On trucks with manual transmission, replace the pilot bearing in the end of the crankshaft if removing the flywheel.
  5. The flywheel should be checked for cracks and glazing. It can be resurfaced by a machine shop.
  7. If the ring gear is to be replaced, drill a hole in the gear between two teeth, being careful not to contact the flywheel surface. Using a cold chisel at this point, crack the ring gear and remove it.
  9. Polish the inner surface of the new ring gear and heat it in an oven to about 600ºF (315ºC). Quickly place the ring gear on the flywheel and tap it into place, making sure that it is fully seated.

Never heat the ring gear past 800ºF (426ºC), or the tempering will be destroyed.

  1. Installation is the reverse of removal. To install the flywheel, first put it into position and then install the bolts loosely.
  3. Torque the bolts a little at a time in a cross pattern, to the torque figure shown in the Torque Specifications Chart.