this is about to be the second flexplate and the fourth starter i have installed in 2 months. whats the problem? Alignment is correct, and ring gear to bendix measurement is correct, battery is new and it cranks fine. The truck is just eating the teeth on both up. The first time it chewed the ring gear and the starter up i replaced both and it sounded like a brand new truck turning over for about a week then one day BAM it tears up the starter up. I take it to the shop and pull the starter only to find the nose cone is broke completley off the starter. How it started I will never know. I dropped the exaust to remove the inspection cove to inspect the flexplate and 5 of the teeth on the ring gear have very small imperfections and they just cleaned up with a jewelers file. This well be the second set of starter bolts i have purchased, they go in strait and when this happens both bolts are bent.
here is a list of thingson the truck that are not stock and all have been on the truck for about 30,000 miles. First off its a 1996 Chevy C3500 4dr Dually 454ci(7.4) Vortec 2wd and 4L80E tranny.
Engine mods. Programmer, roller rockers, and a throttle body spacer.
Chassi mods. Belltech 3in drop spindles and 4in drop shackle and hangar kit.

ask me any question you feel fit and i will answer.