On Thu, 29 Nov 2012 21:24:38 -0700, Richard A Jones <Jones@COLORADO.EDU>
wrote:
<snip>  The front diff, prop shaft and tranny were not all balanced as a
unit.  The prop shaft was (or should have been) balanced by the driveline
shop.  How can indexing it to each end make any difference?  Am I missing
something?
Richard
If the prop shaft has been built by a drivertrain shop, or has had the
ends replaced, it is important that the EACH END is indexed to the other.
It is also referred to as "timing" or "in time."
If it's not indexed, it WILL cause serious vibration. I have seen drive
shafts actually twisted from torque application, putting the prop shaft
out of time with itself.
But it doesn't need to be indexed to any other component of teh drive
train.