[s-cars] 10mm or 11mm hex (allen) key for transmission drain

[Gabriel Caldwell]

My experience was quick and easy, the hardest part was waiting for the
Redline to come in (kind of hard to procure in these parts) and getting
off my butt to buy a 10mm hex key.  The fluid that came out was quite
clean which leads me to believe it was done recently but you never can
be too safe.  That may also explain the relative ease in which I was
able to remove the plugs.  I've read about this mystery additive but in
the owner's manual it says not to use any additives, just GL4 in the
trans and GL5 in the rear diff.  The general consensus seems to be to
just use the Redline products, and that's just what I did.  My method
was to tilt the car to the opposite side to fill it until it overflowed.
Let it sit for a while then dropped it to level to let the extra flow
out.  I then replaced the plug and cleaned up the side of the
tranny/diff.

-----Original Message-----
From: Wayne Dohnal [mailto:wd1 at hevanet.com] 
Sent: May 5, 2004 8:03 PM
To: S-car list; Gabriel Caldwell
Subject: [s-cars] 10mm or 11mm hex (allen) key for transmission drain


I see you already answered the original question.  Assuming you're about
to change the transaxle oil, here's a repeat of a post I made a couple
of years ago after doing the job, which covers various aspects of job.

I changed the oils a few months ago.  Here's everything I can remember!

The car had 130K miles, and the old oil was pretty nasty looking and
smelling, especially the transmission.  So I think it was a good idea to
replace it.  I struggled with what oils to use, and agonized over not
being able to get the Audi mystery additive for the transmission.  After
a lot of input from the list I ended up using Redline MT-90 in the
transmission, and Redline GL5 75W90 in the rear diff.  Everything is
still working fine, and I think the shifting got a tiny bit smoother.

Each unit has 2 drain plugs.  For the transmission you need a 10mm hex
bit, and for the rear a 17mm bit or wrench.  The standard "make sure you
can loosen the fill plug before draining" advice applies.  I found it
easiest to access the transmission fill plug through the left front
wheel well (with wheel removed) and a lot of extensions, but others do
it from under the car. You will drip oil on the cats when you pull the
rear transaxle plug.  You have to remove a plastic shroud under the car
to get at one of the rear end plugs.

The transmission plugs take a lot of torque to break loose, then they go
with a vengeance.  Make sure your hands aren't going to collide with
anything when they break loose.  And don't use Mickey-Mouse tools.  I
twisted a no-name 3/8 extension into 2 pieces trying to loosen one of
the plugs.  On the transmission plugs, my fill plug and one of the
drains had a metal gasket, and the other drain plug didn't (the plugs
are identical). The dealer parts guy says that the gasket doesn't exist.
It seems to work OK either way.

I filled the transaxle via gravity with a several foot long tube.  As
another post mentioned, after it overflows, wait an hour and you'll get
a bunch more in.  Mine took about 10% more than the Bentley lists as the
capacity.  I used a pump to fill the rear diff.

Good luck.  It's not a horrible job, but does take a bunch of time.
After seeing what came out, I'm really glad I did it.

Wayne Dohnal
1994 S4