Terrible noises from 3.0cs 1973
 

I own a 1973 3.0cs and I am hearing terrible grinding noises. I thought it was the transmission, so I did the full 5 speed upgrade. However, when I go up hills, I can still hear this grinding noise and vibrations in the floorboard. Does anyone know what this could be from?

Could it possibly be the drive shaft, or old engine mounts that allow the engine to bang against the firewall? Thanks

I had a 72 3.0CS for 29 years. The engine mounts rot and need to be changed a lot. That could be it. Where in the floorboard area do you hear the noise. And is it constant or speed-dependent?

Please tell me about the "full 5 speed upgrade." I had my 4-speed for the life of the car but would like to know what you did. Is it a ZF transmission?

Motor mounts most likely. Did they replace the driveshaft guibo when you did the tranny?

The last time I took my 76 3.0Si in, the mechanic told me that the severe knocking that was going on under the car was a frozen driveshaft u-joind and failed bearing.