I just went through this valve body voodoo as per Sisler. I had slippage and
poor or no shifting when the van was cool, and it would go away and run
fairly normally when hot- until the day I lost all forward gears altogether.
I pulled the valve body and cleaned it. That in itself is not that big of a
deal, but you have to be sure to be thorough, methodical and to have a very
clean workplace where you can hopefully work undisturbed.
In my case, it didn't help my problem, but it had to be done anyway so it
was worth a try. My main pressure valve and throttle pressure valves were
completely jammed- I had to gently coerce them free. There was plenty of
crap on, in and around the mechanism. I had already reconciled myself to a
rebuild and what I found just confirmed my fears- not to mention the fact
that it didn't work. :)
BTW, there is a fluid filter in the auto tranny- goes right on the bottom of
the valve body, you can't miss it.

Good luck,
Robert

----- Original Message -----
From: "Evan Mac Donald" <macdonald1987@SBCGLOBAL.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, February 23, 2006 7:27 PM
Subject: Re: AT Problem

> Sounds as though you might have a sticky shuttle valve in the shift body.
> It is amazing how small a piece of crud it is that can mess up that part
> of the trans. If you are brave, or at all mechanically inclined, the valve
> body can be easily removed, and cleaned out. I did it to mine just after I
> got it, nine years and 110 K miles ago. Dirt in an auto trans is a big
> problem, especially for us Vanagon mechanic/owners, because there is no
> filter for the transmission fluid in a Vanagon automatic trans. Before
> disassembly, though, you can try any of the available "Miracle in a can"
> trans cleaners. Some even work as advertised.
>
> Mark Erb <kasdtech@MAC.COM> wrote:  1988 Westfalia with 95,000 miles, AT
> fluid changed 25,000 miles ago.
> AT fluid is at the proper level. No AT fluid in the coolant. The
> problem that has cropped up is the transmission sometimes does not
> want to shift into 3rd gear and will wind out until I let off the gas
> for a bit then it will slip into 3rd. The reverse gear will sometimes
> not engage right away then will go into reverse with a big clunk.
> These problems don't always occur but will happen even with a hot and
> cold engine. Anyone else have this problem? Thoughts? A solution
> perhaps? I have easy access to transmission shops (AAMCO, Cottman,
> even a shop that does german transaxles) but I wanted to at least
> have some ideas before I discuss options with a shop or try to tackle
> it myself. Thanks for any feedback. Mark
>
>
>
>
> Evan Mac Donald
>
> 1984 Wolfburg
> 1985 GL 7 Pass.
> 1991 Carat Weekender
> 1972 Chevy P/U
> 1993 Bonneville