Re: how Torsen diff wears?

[Phil Rose <pjrose@servtech.com>]

>
>Date: Sun, 22 Feb 1998 23:09:32 -0500 (EST)
>From: "Graydon D. Stuckey" <graydon@apollo.kettering.edu>
>Subject: Re: Explanation of a how Torsen diff works...
>
>On Sun, 22 Feb 1998, Jeffrey J. Goggin wrote:
>
>> Unfortunately, most of the "tuning" you refer to has to be done during the
>> original design stage ... the only tuning that is available after it's been
>> built has to do with changing the drive v. coast characteristics and other
>> minor characteristics.  That's not to say that tweaking it won't prove
>> beneficial, though...
>
>Its not quite that bad.   You can change its "strength" quite a bit by
>altering the amount of friction in the thrust bearings of the output
>gears.   If this isn't enough, then you are right, you have to change the
>angle of the helix on the worm gears and thats a pretty major machining job.

Just this morning I read (OK, I skimmed) the very interesting Gleason
article on the Torsen diff. design. Thank you Jeff (Goggin), for putting
this on your website.

Anyway, now that I've read about the function of the thrust washers
(bearings) that Graydon referred to (abov), I wonder if these are a normal
"wear" item. Will these washers tend to wear and cause the friction to
change over umpteen+ Kmiles of use--i.e., to the extent that the
performance characteristic of the Torsen diffs might change significantly
from the original factory spec? Is there a testing procedure? Is it unheard
of to have (or need) a Torsen diff. repair for this? I don't seem to hear
much at all about Torsen diff. problems. (Praise be to Audi gods!)

Phil Rose
Rochester, NY
Birthplace (I guess) of the torsen differential

Phil Rose		Rochester, NY
'89 100			pjrose@servtech.com