i have a 2000 ss, and when you try to put it in 1st gear above 30 it makes this grinding noise and wont let you put it in first, and when it gets below 30 the grinding noise stops and it will go into gear, is this normal, is it schronized?

 

its fine, they all do that. just don't put it in first if ur rolling, thats how you bend pushrods....