I have a 2008 chevy 4 wheel drive and only when it gets to temoature of 210 not when its cold u pull it in gear it sets there u bump the gas pedal it jerks and shifts perfect and down shifts no slipping

What is your question?

And u hear a faint knocking noise

What makes this problem better or worse?

No when it 210 it only does it not all the time

How long has your 1999 Chevrolet C1500 had this problem?

few weeks