Rear axle problem?

[ViaJoaquin@xxxxxxx]

That bell ring clunk is a classic symptom of a bad u-joint, check all of them 
and replace any with detectable play.
As for the latency of the wheels turning when the pinion is turned as opposed 
to the pinion turning immediately when the wheels are turned, you have to 
bear in mind that there is a gear ratio at work. Most 60's IMPs have roughly 
a 3 to 1 ratio in the rear axle. That means that for every one turn of the 
pinion the wheels only turn one-third of a turn! And for every one turn of 
the wheels, the pinion turns three times. My point here is that it is a lot 
easier to detect the pinion turning by turning the wheels than the other way 
around, especially since the wheels and tires are ten times the diameter of 
the pinion flange! The only real way to detect slack is to have one hand on a 
tire while your other is on the pinion.

Roy
67 Crown FDHT

In a message dated 3/2/2002 7:27:10 AM Pacific Standard Time, 
roscoe1@xxxxxxxxxxxxxx writes:

<< Our '64 has an 8.75" sure grip differential.  I have the car on jack 
stands and the drive shaft removed.  When I rotate the rear wheels I get 
almost instant movement of the pinion flange, but when I rotate the pinion 
flange there is much more "slack" before the wheels begin to turn.  It seems 
to me that the amount of "slack" should be the same regardless of which "end" 
I am rotating.   Is this behavior normal for the sure grip rear-end, or do we 
have a problem?
 
 I am trying to find the source of a "clunk" in the driveline, when I shift 
out of neutral into reverse or a forward gear.  The "clunk" is kinda loud, 
and has a sort of bell ring sound to it.  The front U-joint is a bit lose, 
but side-to-side not rotational, as though the ends of the "cross" were worn. 
 I will replace it anyway.  Also sent the center support bearing insulator to 
the Damper Doctor for rebuild.  The rubber was intact, but sagging due the 
car sitting idle for 12 years.  >>