Date: Mon, 4 Sep 2000 09:35:16 -0700
Reply-To: aatransaxle@JUNO.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Daryl Christensen <aatransaxle@JUNO.COM>
Subject: Re: an auto tranny question
Content-Type: text/plain
Most times when they service a VW trans , they only drain what ATF they
can get out of the pan...They should also drain the Diff section..the big
problem with these trannys (other than weak clutches from too small a
trans in a heavy rig) is the seals between the diff & the trans tend to
leak and the ATF gets into and dilutes the 90wt in the diff. There is
less pressure in the diff side so that's why the ATF gets in there. I
haven't seen a reason to use anything other than plain old 75-90wt in
these diffs...They wear well unless they are run low or diluted....MT90
may be overkill and I never heard of anyone usng it, but I guess it
couldn't hurt...On many US vehicles a tranny shop can flush the ATF fluid
using a flushing machine or use the cooler hoses to get more out...not so
on VW stuff...My recomendation is to remove what you can from the trany
pan once a year (only about 2 qts) and doing this will gradually flush
all the ATF and keep it happy...There is one school of thought that says
if a tranny has over say 150K on it and has the original dirty crummy
fluid in it still..that the new stuff will start to eat the clutch
material fairly quickly.....who knows...I do know that changing any OLD
gear oil with new will improve the life expectancy od s manual
trans...but when it comes to auto trannys...your guess is as good as
mine...I flush my own rigs every 30K...Daryl
Daryl of AA Transaxle
Duvall, WA.(Seattle area)
(425) 788-4070
1-877-377-0773 toll free
http://www.aatransaxle.com (web site)
On Mon, 04 Sep 2000 00:02:18 PDT "Mark Dorm" <mark_hb@hotmail.com>
writes:
> I've had a transmission service done, and I know they changed the oil
> - but
> does that mean they changed the ATF too.... I remember them saying
> they
> can't drain all the oil, and they said it looked like it may never
> have been
> changed, so they recommended to put to some again (before the next
> transmission service) to clean it out.... and I remember being told
> something about the different fluids mixing and that was another
> reason to
> change the oil more often.... So my question is, does this mixing of
> fluids
> always take place (you note: ATF into the Diff), or is there
> anything I can
> do about?
>
> And if the rarer case of 'Diff into ATF' occurs, am I better off
> with the
> Usual Stuff as opposed to MT-90, or am I f'd either way?
>
> Thanks Daryl!
>
> >From: aatransaxle@juno.com
> >
> >I would think it would be OK to use in the final drive...The only
> >downside would be if the seals separating the halves were weak and
> the
> >oil transfered to the ATF section,b ut that would be rare..the oil
> >usually goes the other way (ATF into the Diff)
> >
> >On Fri, 1 Sep 2000 21:42:10 PDT Mark Dorm <mark_hb@HOTMAIL.COM>
> writes:
> > > Darly, would you put MT-90 in an automatic???
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