[s-cars] V8 Torsen Diffs

[Dave Forgie]

Bob:  Yay!!  Somebody actually knows the meaning of yellow and green and AFV
and AXZ!!!  I was wondering what the big indent on the top of the casting
was.  Now I know.  I now also know that I have a post 1990 V8 torsen diff
because the vent is low and on the left side of the casting.  My concern was
that I may have inadvertently got a 1990 Automatic V8 torsen diff. But that
is not the case (no pun intended).

I did count the input turns to output turns yesterday and got something very
close to 4 and a bit (no degree wheel) in on the driveshaft flange  to 1
turn out (on the axel flanges).  So, for sure, I am a happy camper.  Now to
install it using Igor's install hints from Dec. 19/04.

Dave F.

Robert Rossato wrote:

> > Bob,
> > mine came off a 1990 V8. The case appears to be identical to
> > the OEM in
> > my 1997 UrS6.
>
> The difference is subtle.  I have an AFV rear differential, which came
> out of a '90, and an AXZ, which came out of a '91 and was used in all
> subsequent years.  On the '90 (AFV), the vent is centered at the very
> top of the housing recessed within an opening in the casting.  On the
> later diffs (AXZ), the vent is moved to the left side of the casting and
> sits slightly lower overall.  The original location of the vent is still
> evident in the newer castings but is obviously sealed.  I assume that
> the casting on the EDL diff from your '97 would have the later vent
> location.
>
> With regard to Dave F.'s question on the green vs. yellow markings, I
> took a closer look at the FA and determined that those markings are
> related to the propeller shaft somehow.  On the V8 there are two
> different prop shafts spec'd, also differentiated with a green vs.
> yellow marking.  The only thing in the remarks column is that the green
> one is designated with a "0.00 - 0.04mm", and the yellow one is "0.04 -
> 0.08mm".  For the life of me I can't understand what would need to be
> toleranced so closely in the interface of those two parts that .04mm
> (0.0016") would make a difference.  For yucks I checked the FA for the
> S6 diff and that also shows two different ones with green and yellow
> markings, however, there is only one prop shaft available.  Go figure.
>
> Bob