oscillation vibration?
 

I used to own a 76 Chev 4X4, it was full time when I bought it, I installed the conversion kit and put locking hubs on it.

This truck had this oscillation vibration at certian speeds, I think it was it was only in a 5 MPH range around 60mph, anything above and it would stop, anything below and it wouldn't do it ether. it did it before and after my mod.

The vibraton was kinda like 4 seconds on and 4 seconds off, just a steady rhythm intil I changed my speed.

I know what a tire feels like, its a steady vibration at certian speeds, so I allways figured it was in the drive train somwhere but never figured it out.

Anybody experiance this and know what causes it??

Re: oscillation vibration?
 

im gonna watch this one closely!! ive got the same thing in my 89 from 30-35, mines a little faster but it is the oddest vibration ive ever felt.... and im a GM dealer/ASE certified mechanic!! im starting to think driveshaft in mine

Re: oscillation vibration?
 

Worn rear axle?

Re: oscillation vibration?
 

My father in-law's 94 Blazer did the same thing. Apparently it was something in the transmission, once the tranny got replaced it stopped doing that. I have no idea what in the tranny caused it. If you get out of the throttle and back on again, does it stop? That's what his did.

Re: oscillation vibration?
 

Come to think of it, I've fixed that by tightening an output yoke nut....