Notice that most Flexplate Assemblies fail due to installation error and/or balance problems that could be within the engine or transmission. Below are some, but not all the causes:
Not installing Flexplate Assembly perpendicular to crankshaft flange.
An out of balanced engine and or torque converter.
Worn front pump bushing.
Too much end play on the crankshaft due to excessive thrust bearing wear.
Not torquing bolts to proper specification and in proper sequence.
A bad starter drive can cause teeth on right gear to wear rapidly or break off. Also, teeth can chip or break when engine is running and the starter is engaged.
On some GM applications special shims are needed to properly align starter with the Flexplate Ring Gear teeth. In such cases where shims are needed and not used, damage to the right gear will occur.
