I have a sound coming from 84 K20 4x4 pickup. I have not been able to identify what exact it may be, but today I found my driver side drum brake is leaking. The sound I am trying to identify if more of a hollow clunking sound. As if rocks were inside an aluminum fence post and as if you were unwinding barb wire wrapped tightly around an aluminum hollow post. I have never heard this sound come from a vehicle before. This sound is created in low gears before 2k rpm is achieved and then disappears until stopped and started again (so 1st or 2nd gear). If you let off the gas the sound disappears, when you throw it in neutral the sound will stop. As of today in speeds excess of 45 or more it feels like it's in too high of gear as it feels boggy. There is no play in the transmission it shifts great.
I will have the rear drums off tomorrow for new shoes and possible a wheel cylinder.
Any suggestions on what may be my issue? I need to get this resolved soon as it is my part getter for the goat. Any help is much appreciated.
1970 GTO 455HO Cardinal Red