[67John]

I have this noise/vibration at 3K RPM's. It's a 67 Mustang with an automatic. I have replaced everything from mounts to U-joints and rear end. I recently installed a Gear Vendors overdrive and the vibration got worse. It is a drive line issue, not speed related. It will do it in any gear and go away if you take it out of gear and coast. It starts at around 3K and goes away soon after. I hear it and feel it in the body, steering and seat. Any ideas?

 

[AzPete]

Have the driveshaft checked for being out of balance.

 

[MSTONE34]

From your description, I think you will find the slip yoke worn out. This will cause the exact problem you describe.

 

[mustangfactory]

Tail housing bushing is a very common problem, grap the yoke and see if you get play, if so it maybe the bushing or the yoke

 

[manley]

I had a worn pinion yoke do something like that. One of the u-joint caps was loose in the yoke.

 

[Mustangerbob1]

UH-1 Helicopters chasing you.

 

[jmagilto]

WHeel Bearings anyone?