HELP! 99% complete frame off restoration 1972 chevy K20, 402 BB (rebuilt), T400 Auto
Metallic sounding humming sound, constant between the speeds of 34-45ish mph. Does not change with gas pedal or what gear its in.
What's been addressed so far and ruled out:
-Transmission
-Rear-end
-Speedometer cable
-Tires, obviously...
-Open-ended tubes of metal side steps
Anyone had this random problem before, please help!
Thanks,
Asa