Originally posted by markzeronine
change your tranny fluid with gm syncromesh(sp).
a little pricey, like 30-40 for 3 quarts, but saved my tranny(i was grinding into 3rd)
#!@#!#@!@# i have the same problem now, under high rpms when i quickly shift i grind in only 3rd gear i figured it was syncros gone but i can still save?!@!@?!