GM S10/S15/Sonoma Pick-Ups 1982-1993 Repair Manual



On most of the engines covered by this manual the flywheel and the ring gear are machined from one piece of metal and cannot be separated. On some of the engines (4.3L engine) the ring gear is a separate piece and can be driven from the flywheel once the gear is heated using a torch. If attempting this, first make certain that the ring gear is a separate piece, then uniformly heat it around the entire circumference. DO NOT heat the gear until it is red hot as this will change the metal structure.


  1. Remove the transmission assembly from the vehicle.
  3. If equipped with a manual transmission, remove the clutch and pressure plate assembly.
  5. Remove the flywheel-to-crankshaft bolts, then remove the flywheel from the engine.

To install:
  1. Inspect the flywheel for cracks, and inspect the ring gear for burrs or worn teeth. Replace the flywheel if any damage is apparent. Remove burrs with a mill file.
  3. Install the flywheel. Most flywheels will only attach to the crankshaft in one position, as the bolt holes are unevenly spaced and/or the crankshaft is fitted with a dowel pin. Install the bolts and torque to specification using a criss-cross pattern.
  5. If equipped, install the clutch and pressure plate assembly.
  7. Install the transmission assembly.