I have a 1984 Monte Carlo with and engine swapped to a 350, I have had a bad knocking that is not coming from the engine, it started when I smashed the gas getting on the freeway, its a steady knock that gets faster and louder the more my RPMs and Speed increase, but it only occurs while in Gear, shift it out and its gone. I have replaced my Transmission Mount and then both U-joints on the Drive shaft thinking that it was those, the Knocking is still there. Anyone Please some answer or places to look would be great.

 

try to get you some help started.......overall and comparative, how does the engine run?

 

flywheel bolts tight? that can make a lot of noise at different times.