My dizzy gear was worn worse that that one, mine was on the verge of breaking.
The only indicator on my truck was that it would pop slightly when at cruise speed, felt like a miss.
There is a distributer mod that allows more oil to fall onto the cam gear. Insufficient oiling, bad design/manufacturing of teh dizzy gear can all come into play.
Why it didnt show symptoms 1st, i really dont know.
The good thing about this whole situation is that the camshaft is made from induction hardened steel, so the roller lifters wont gall into the lobes of the cam. Since teh cam gear is so hard, a special dizzy gear made from softer melonized metal. The idea is to have the dizzy gear wear instead of the camshaft gear(for obvious reasons).
this is an EXCELLENT billet replacement dizzy for the 96-02 Vortec 305,350 and 454.
http://www.jegs.com/i/Accel/110/60116/10002/-1
more info on teh Billitech dizzy
http://www.pacificp.com/forum/viewto...r+oiling#26482
You are supposed to be able to grind in vertical grooves into the dizzy to alow for better dizzy gear oiling.
peace
PAuly