Tom,
Here's another shot..... Check the amount of slop between the front
yoke and the transmission case extension bushing. It is easiest to do with
the drive shaft off the rear end-just try to wiggle the yoke inside the
extension. You shouldn't be able to move it side-to-side inside the case.
Could be you have a worn bushing and the slowing speeds are causing the
front yoke to vibrate in the case extension.
I had a wicked shimmy coming from the tranny that only occurred from 35-55
mph. I had new tires and wheels so I decided to replace u-joints and get
the drive shaft balanced...still had the shimmy. I then took off the drive
shaft and was able to move it 1/4" sideways. Like an idiot, I threw away
the bushing (looks like a sleeve) when I put in a new rear tranny seal and
the yoke was being supported by the tranny extension...this is bad. The
bushing was loose and had worked it's way out of the extension and past the
rear seal, so I thought it was a sleeve to protect the yoke from rust.
duh, check the repair manual next time.
good luck,
Adam
'55 2nd 3600
> I am experiencing severe drivetrain vibration. This happens only when I
> let off the gas at freeway speeds and does not occur during acceleration.
>
> The vibe seems to come from the tranny area and on back.
>
> I suspect bad U-joint(s). Can anyone confirm these symptoms?
>
> Tom B. 57 Stepside 3200
>
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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