Building a better Vanagon automatic transaxle

[vwhammer]

[Gruppe B]

[vwhammer]

Actually if you think about it the direct drive clutches have more strain on them because there is no gear reduction.
At highway speeds it might be easy to maintain momentum but in town where your speeds are slower but the trans still shifts into 3rd gear would likely stress them out pretty good.

Toss a low fluid situation into the mix and you are sure to have issues.

[vwhammer]

Still waiting on some parts but I made a little progress.

My diff section arrived.

Figured I would give it a coat of paint.

Also painted the trans case.

I painted a diff cover and trans pan that I will install after I am done dragging the trans all over the floor while trying to get it installed.

Got some high flow banjo bolts and fittings for the oil cooler.

Started to clean up some parts to start putting all of the new parts in.

Decided to start with the forward drum and clutch assembly.
I decided to go with the Audi unit because, as I mentioned before, I know how many miles are on it and it appears to be in better shape.

Upon further inspection it appears that this is the clutch pack that has one extra friction compared to the Vanagon assembly.

Everyone kept saying that there was an extra friction somewhere but no one ever seemed to point it out.
Now we know or at least we know that my particular trans came with 5 instead of 4.
I also noticed that the top ring in this drum is different than the van part.

Audi on the left van on the right.

You can also see the 2 grooves in the drum in that pic that do not exist on the van drum.
h00drat also pointed out these grooves and wondered if they are supposed to be there.
Once again, now we know.

So back to the clutch packs.

the Bently for the van shows 4 frictions in both the forward and direct drum but all the other exploded views that I have seen show 5 frictions in both the forward and direct drum.
To make things even more confusing I have 2 sets of new frictions for the forward drum and both have 5 frictions in them.

Weird.

Either way, externally the forward drum appears to have the same dimensions between the Audi and the van so I am going to assemble the Audi unit with the extra friction and hope that it works.

Another thing that confuses me is that my first intermediate clutch from the van has one extra steel that looks like some kind of wavy spring washer.
The Audi does not have this steel.

Anyone have any input on any of this?

For reference here is a trans diagram that was posted back on page 14.

I think I am just going to assemble all the Audi bits as they were when I removed them from the Audi trans and see if it all works in the van case.

I fear that it may all fit but then I will get it all installed and it does not function as it should.
I will be pretty bummed if I have to take this trans back out.

[danfromsyr]

iirc #604 in the chart is differrnt tween the audi and the van. the splines are different spline count.. you need to retain the vanagon one to match your vanagon turbine shaft (#673) which is different than the audi one
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[AtlasShrugged]

IIRC danfromsyr is correct. I seem to remember just swapping Vanagon #604 over to the Audi part.

[vwfreek61]

[danfromsyr]

interesting..
we've had banjo/barb fittings on a few w/o incident.. maybe your hose clamp didn't clamp properly? I do like the Pushlock fitting option and will print that to keep in/with my ATF parts.

as iirc there's not really any pressure in those lines. doesn't the cooled fluid return drop the into the base/pan and not a high pressure system?
This is why if there's a failure in the oem coolant heat exchanger that coolant migrates into the ATF (coolant pressures are 10~15psi)

maybe VWhammer can confirm where the cooler return line returns to in the housing.
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[AtlasShrugged]

Those ATF lines do have full pump pressures. The bottom fitting comes directly off the outlet of the ATF pump, in the back of the housing. The top fitting ATF goes into the transmission. See the PDF:


http://www.volkspage.net/technik/ssp/ssp/SSP_8.PDF

[vwhammer]

Wonder what kind of pressure that pump produces in that line.

I do not recall having any issues with plain old barbed fittings for things like this.

I have a repair in my air hose with a barbed coupler held with oetiker clamps and it is at 100 psi all the time.

As with anything, things can happen.

[vwhammer]

[danfromsyr]

is Alika T3 detailed and image intensive thread cross linked in here?

https://www.thesamba.com/vw/forum/viewtopic.php?p=8398509
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[AtlasShrugged]

[vwhammer]

[danfromsyr]

once these go to scrap, they're gone for ever..


if anyone is near Sun Valley, California and wants the HD 4 planetary gears
there's a good price on a 944 automatic
$210 picked up
https://www.ebay.com/itm/1986-1989-PORSCHE-944-AUT...3572381454

or in Orlando, Fl
$350
https://www.ebay.com/itm/PORSCHE-944-AUTOMATIC-TRA...3812247451


$550 in Rockwood, California
https://www.ebay.com/itm/1988-Porsche-944-Non-Turb...4196927330


or a pair of them for $300ea in Scottsburg, Indiana
https://www.ebay.com/itm/Porsche-944-Automatic-Transmission-126/223523400128

https://www.ebay.com/itm/Porsche-944-Automatic-Transmission/223531716663?hash=item340b875037
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[puchfinnland]

I rebuilt my Transaxle earlier this spring w the Audi Turbo parts,
I was told by a very reputable Vanagon transaxle builder

make sure you use OEM pistons, the 3 big ones.
-they are very costly, if you are still quick you can get them from PORSCHE with the same part numbers, as of the spring there were only around 14 sets still avail from germany, and when they are gone they are gone...forever.

make sure you replace all the bushings (except for the impossible one)

It appears my back-to-back seals are leaking,they are new, I need to go back in and re-replace them, this time i will use a very thin plastic liner to slid them over the shaft, I can not really believe I damaged the new seals.

I was also told to replace the seal inside the diff, that keeps the gear oil from leaking at the converter end, this requires dis-assembly of the diff to get to it.


Use the AUDI valve body as it may be running the transmission at a higher pressure to make better clamping force and crisper shifts, if you introduce a stronger engine this will be clear.

[h00drat]

Hi all,

After about 3k miles of joy, I'm back with some less happy news.

About a week ago I noticed a slow shift between 2nd and 3rd. As you can imagine, this made me quite nervous. After talking to AtlasShrugged I concluded that I might need a fluid change, and to flush out and replace the Type F ATF I was using. Going way back, this is the Terry K method, and if this was my demise, then shame on me.

At any rate, I ordered a trans service kit and planned on doing a few flushes to get the Type F out of there and the new synthetic ATF in. Before I could get to it, I was driving my son to school yesterday and the trans started whining, then I lost all gears. Forward and reverse.

On my lunch break I figured what the hell, so started it up and I had D and R again, however still some whining especially in reverse. For obvious reasons I didn't actually drive anywhere, but confirmed that I at least had movement (forward and back).

Fast forward to last night. I dropped the pan to see how things looked. On the plus, no large chunks of materials or obvious signs of broken parts. However there was a fair amount of silver "dust" in the fluid (see images). No signs of gear oil in the ATF either, thank God.

My best guess is that the silver dust clogged some passageways in the transmission...but I'm a newb, so that's a complete guess. I am cautiously optimistic, but want your POV.

Curious what you all think...

1. Are my clutch plates toast and in need of another rebuild?
2. Will a fluid flush potentially get me back on the road and happy?
3. If yes to 2, should I go ahead and pull the valve body to get it as clean as possible inside?

If this is normal wear for NEW clutch parts, perhaps it should have been on my radar that I need to flush and swap fluid soon after a rebuild. Just wasn't something I considered. If it's not normal wear, what would have caused it, other than potentially the Type F ATF? Terry K claimed that he ran Type F for many many many miles and never had issues.

Any other advise welcome. Pictures for your viewing pleasure.

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<<Tyler>>
1987.5 Wolfsburg Weekender / CHC / 2.0 ABA
CHC Top Thread
Engine Conversion Thread (2.0 ABA Swap)
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[mikemtnbike]

that stinks hoodrat- especially since I think your van was up for sale, frustrating I'm sure.

My transmission is currently getting rebuilt, albeit it for different symptoms (sticking in 1st gear for first minute or two after start-up, then shifting great after a little bit of warm-up). I decided to just get it rebuilt as it has well over 200k on it with unknown history and I hope to put a more powerful engine in within the next year or so.

Anyway...I also used Type F when changed fluid about 6 months ago, hoping to stretch the life out of what I knew was a tired tranny. Totally different symptoms, but I too am afraid the Type F could've hurt rather than helped.
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1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[vwhammer]

I am no trans expert but that looks like an awful lot of debris for normal break-in and/or wear.

I would flush as much as possible and probably drop the valve body to get it all cleaned up.

The trick question here is what came first, the issue or the debris.
Was it a larger piece of normal break-in debris that maybe got stuck in the valve body?
This could have reduced pressure on a clutch to the point where some slipping was happening causing more debris but might not have caused any drivability issues.

Naturally this would create more debris to the point that it starts screwing thing up that you actually notice.

OR was some slipping happening because of perhaps the wrong fluid or a slightly out of spec assembly.
This obviously would also cause more debris which might then start to cause problems.

Once again I am no trans expert but I would guess the valve body will need a good once over.
The only thing that I can think that might make a wine in the trans would possibly be one clutch pack still slightly engaged while another one is trying to do it's thing. (likely from debris in the valve body)

Maybe you will get lucky and find a bum seal or spring in the valve body that started the whole issue in the first place.

And at least when you drop the valve body you will be able to see at least one set of clutches and maybe gauge the wear on those.

I guess the other obvious thing to look at is making sure none of you linkage got knocked out of wack.
It is my understanding that this can cause all sorts of problems.

All of this may be obvious but I am just tossing things out there in the hopes that it might lead down that right path to a cause and solution.

[h00drat]

Those are all good questions, and I wish I knew the answer to them

At this point, I agree with your recommendation of taking the valve body out and A - give it a good cleaning, and B - looking at the clutch packs that I can see for wear.

I don't feel like any of my linkages are out of wack, but can check.

What is most bizarre to me is that it took 3k miles for this to happen, then it just came out of nowhere. It makes me think that there was potentially "normal" wear that may have plugged something up, causing the slippage, leading to faster wear over the last week?

But again, the last time my transmission started slipping, prior to the rebuild, I think I drove it for an entire year before it went out. At the time I think I also had gear oil making it's way into the transmission.

The fact that this went from a slight slip to no gears in 1 week is throwing me off.
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<<Tyler>>
1987.5 Wolfsburg Weekender / CHC / 2.0 ABA
CHC Top Thread
Engine Conversion Thread (2.0 ABA Swap)
ABA Swap - Image Gallery
Auto Trans Rebuild - Image Gallery