Date:         Fri, 3 Mar 2000 16:18:18 -500
Reply-To:     ehall@TOGETHER.NET
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Ezra Hall <ehall@TOGETHER.NET>
Subject:      Automatic Transmission, slipping when cold?
Content-Type: text/plain; charset="iso-8859-1"

Folks,
 I think there is a problem with our automatic transmission, or perhaps the
torque converter on our 1988 Westy. On cold days (freezing or below), it takes
a while for power to be delivered to the wheels, something is slipping. I have
not changed the atf fluid since purchase last fall, but the level is ok. I performed
the "stall" test as described in the Bently. This test consists of applying
the brakes while in Drive or 1st, and briefly flooring the engine while monitoring
engine RPM's. MAX RPM's are supposed to be an indication of torque convertor
and/or trany health. On our westy, RPMs reach ~2800-2900 according to the dashboard
tach with a warm trany. I have to check the trany code to see if this is within
spec, there are different specs for different tranys. I suspect the difference
has to do with engine power more than anything else (later engines have more
power), but I didn't track down the trany codes to correlate to year.  The Bentley
manual indicates high RPM's are a sign of slipping first gear plates (There
is no difference in RPM's if in D or ist).
 While driving  power delivery to the wheels seems ok, once the engine has idled
for a minute or two or course (longer if it is really cold out). Fuel economy
is ~14-15mpg. I expected fuel economy to be in that range given the vehicles
size/weight/underpowered engine,etc.. but do folks see better fuel economy than
this? If driving on level road at 50MPH, and I floor the engine, RPM's increase
300-400. Of course some loss will occure in the torque converter since it doesn't
lock, but is this an exceptable amount (~10%)?

 The Bentley indicates if the "stall" RPM figure is below the spec range, the
torque converter is shot. I suspect if it is slipping too much, it could also
cause the "stall" RPM to be too high as well? Is the torque converter on the
way out? Does the torque converter have its own fluid internally, or does it
somehow share atf with the trany? If so, could changing the fluid help? Is a
locking torque converter available? Perhaps from an Audi?
Thanks!
 Ezra Hall
'88 Westy
'86 944
'95 Golf (soon to be sold)