AT transmission shifting weirdness

[Wildthings]

[AndyBees]

As Dave stated, that's a fixed shaft supporting the Torque Converter (one-way clutch support is what it's called). A triangle file might clean up those splines, however, they may be fine as is. Seating the TC onto the shaft should result in a 10mm clearance of the end of the pilot (boss) from a plane straight across the bell housing. It should rotate freely when fully seated.

The Torque converter pilot (boss) "centers" in the end of the crankshaft for installing the three bolts that secure it to the flex plate. The flex plate is bolted to the end of the crankshaft. So, it's highly unlikely there is an alignment problem.

The bushing in the end of the TC obviously appears damaged. Most likely that's the source of the sparkly metal in the screen/filter.

Looks pretty obvious that the seal install was botched.
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[Wildthings]

[Wildthings]

To blackglasspirate:

What letter is stamped on the mount boss on your torque converter? Should be an "H" or a "Z".

You should consider using some kind of automotive goo on the exterior of your TC seal. Some seals tend to wander if not glued in place.

[AndyBees]

[MarkWard]

Bummer, the outer splines are from memory are the torque converter stator support. Again from memory, unlike the Audi, the splines are part of the differential housing which is unique to the vanagon and maybe later busses.

You will need to determine how much of the splines are needed for the torque converter. Normally the torque converter slides all the way in and moves out when attached to the flex plate.

This is not a good outcome. The seal probably cocked while the torque converter was rotating off center. Inspect the flexplate. It was seeing loads it was not designed for. Glad you found something, but not exactly a common failure.
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[AndyBees]

Mark, that's what I was thinking after looking at the pics in the other Thread as well as my two Bentleys (Quantum and Vanagon). The shaft is the stator support and part of the diff housing.

My Bentley for the 87 Quantum has far better pics and narrative than the one for the Vanagon.

Seems in the other Thread that I linked, you mentioned that these bushings are not offered as "spare" parts. Not a good circumstance to be in.

Yeah, I agree there must be something going on with the flex plate.
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[Butcher]

If the mechanic is any good, he's going to check that shaft with the new bushing. Those photos show that shaft has had better days and short of flame welding it, I think you're going to need another one.

With all the abnormal wear marks on the oil pump shaft and stator shaft, something does not appear to be aligned properly.

Either way, I think you have found the source of your troubles. Once the transmission is completely taken apart, then you will what else was ruined.

[blackglasspirate]

Yeah, not exactly the best news or what I wanted to find when taking this apart.

Wildthings: I can't find any letters stamped on that TC. It's currently at another shop right now where they are removing the bushing so I'll check again later. It's a rebuilt I got from Precision (through GTA).

Interesting to know that is a fixed shaft and part of the differential housing. The chances of finding another housing down here is close to none. One thing that I don't think I got a good picture of was there was a protrusion from that shaft where the bushing was riding. It was just a little piece of metal sticking out and you can see the groove that it wore into the bushing. No idea how that got there. We just filed that down and used some extra fine grit to smooth out that shaft and the splines.

The guy who has the TC right now is confident he can replace the bearing with one that will work and will hopefully test a fit later this afternoon.


I would not be surprised if the mechanic who did my peloquin differential install in the States had something to do with this. I started having doubts over the course of the work and he was having a lot of trouble with the TC and seal. Who knows, maybe it was something else but seeing this sort of damage around the TC doesn't completely surprise me after that.
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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee

[blackglasspirate]

This is what the shaft looks like cleaned up a little.

I "inspected" the flex plate visually but didn't really see anything that stood out as wrong.

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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee

[Wildthings]

[MarkWard]

I have not done this before, but some members have suggested using 2 torque converter seals. I agree with dressing the splines as much as you can. The working section is the outer splines, but you need the torque converter to move as smoothly as possible across the splines. Are you reusing your torque converter with a new bushing only? If so, you really need to look at the 3 sets of splines in the torque converter. Flex plate would start to crack out from the center where it bolts to the crankshaft.
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[AndyBees]

The TC must slide in deep enough on the fixed splined shaft to provide 10mm clearance on the other side (Flex plate side) at the center pilot (boss). The 10mm clearance is from the end of the pilot to an imaginary plane from one side of the bell housing to the other.

I believe we have the rest of the story...... installing the Peloquin Diff. I'm going out on a limb, I bet they jammed the TC with the center shaft not fully set in the Oil Pump which is on the extreme back end of the Tranny. They may have went as far as to start the engine and heard strange noises. Then, they may have dropped the tranny back out to correct the problem... left a bummed Seal and damaged bushing(s).

The inside of the TC contains at least two thrust bearings and the Stator is spring loaded. The Stator has a bearing. The Stator stops rotating when the vehicle is not moving (the Impeller and Turbine continue to rotate). It begins to rotate (slowly) as acceleration commences. It's purpose is to increase Torque out put from a start.
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[MarkWard]

I believe you can change the differential carrier on a vanagon automatic out the bottom pan without pulling the transmission.
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[blackglasspirate]

Thanks for the replies, as always. And for the details on the inner workings of this transmission and its parts. I've always wanted to take one of these apart and learn more about them, just under different circumstances

So, as far as the splines go, I do plan on addressing that a little more. I dropped off the differential section and TC at a machine shop today that my mechanic says does great work. They are working on the bushing and possibly the splines, but first the bushing. That is supposed to be done by midday tomorrow.

I did hear about the ability to remove/replace the diff without dropping the trans. Though, now that I think about it, I don't remember why we dropped the trans anyway or if there even was a reason. That was a high stress time of getting ready for this trip so it's all a blur.

I have also heard about the 2 TC seal approach. For that reason I bought two TC seals to carry with me on this trip. However.....it got nice and damp here in the van a few times and the outer metal parts of the seals developed some surface rust. Not sure if that will affect the integrity of the seal but I hope not because the kit that I bought did not include the TC seal and the one that was in there is hosed. I'm not sure if I'll try the two seal approach or not, but I need to read up on it a little more.

As far as the TC itself goes, yes, I plan on re-using it. At this point, I don't think I have much of an option, short of waiting a while to import one. I do want to attempt to flush it as best I can, but I don't know if I have any other good option for now.


I did receive the rebuild kit and brake band today and took a look at the disassembled automatic section. The brake band ended up looking fine for the most part, but I'll replace it anyway. The problem the mechanic brought up was the discs (clutch/friction discs? not sure the correct terminology). They were a bit worn, but more importantly looked/smelled burnt. From the looks of it the ATF level got too low and burned them up. My guess is the botched TC/seal install eventually produced the leak, then the leak started causing the other problems that eventually led to the burnt discs and more. At this point there hasn't been anything else inside that trans that indicates other problems.

As it stands right now, the TC/bushing work is supposed to be done tomorrow midday. The auto section should be done by the evening. If all goes well we will be reinstalling and test driving on Thursday but that may be a stretch. You never know what else will happen between now and then. In the meantime we are staying in the mechanic's driveway and getting used to sleeping in a half upright position from the van being on ramps. There's wifi, power, cold showers, and beer....so it could be much worse!
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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee

[jberger]

I would hate to see you go through all of this and try to reuse the stator "fixed" shaft as well as the same TC. It is obvious the shaft surface on which the TC bushing rides is farked.. Short of high speed precision polishing on a rig similar to a Crank grinding lathe... I wouldn't reinstall. Once that is replaced or "fixed" you HAVE to get a different TC. It is certain the existing unit is defective. The stator support bushing is the ONLY thing you can see. If you are looking at this as a stop gap\bush fix then I get it. At some point it will have to be fixed properly.

J

[Butcher]

I agree with Jberger, but I also understand the mechanic will not let you sleep there for months before the good parts show up.

I would make certain the bushing has the proper clearance before the bushing is installed in the converter. I do not think you could measure it with everything installed.

As with all automatics, once you loose pressure, clutches slip. Then things get hot. If you could have installed a pressure gauge during the diagnosis, you would have seen that. Obviously you are in a place that does not have the tools/knowledge/parts to maintain your Vanagon. I hope this is the end of the major issues.

Maybe it's time to buy a local car, something that someone can fix. Use the Vanagon for the nice days.

[blackglasspirate]

Well, the plot thickens.

Went to pick up the auto section from the rebuilder yesterday and it was still all in pieces. The problem was the pistons in the clutch packs. The rebuild kit didn't come with pistons and according to him these pistons are supposed to have more of a lip/flare on the edge, otherwise they won't hold pressure. I don't know what they normally look like around the edge so I have nothing to compare it too. The rubber material around the edge is still soft - not burnt or hard. I also asked GTA about the pistons but for whatever reason they haven't been helpful at all through this whole process.

Either way, he basically said he wouldn't put it back together as is. After some frantic searching/calling around, I was able to locate some in Santiago. Unfortunately for me it's Easter weekend and everything will be closed starting tomorrow until Monday, so I'm not going anywhere.

I did get the TC back and the bushing fits like a glove. Hopefully that works out. I understand everyone's concern about that and if I were back in the States then I would go about it in a different way, but getting a whole new differential housing with that fixed shaft is not an easy or cheap thing to do. There seem to be mixed opinions on that shaft and if it's ok to go ahead with using. Still figuring it out.

As far as buying a local car and using the van for weekends, that's unfortunately not an option as I live/travel full time in this thing! I'm not a Chilean/Argentine resident. Just here for a few months before heading to the next country.

Here are pics of one of the pistons.

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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee

[MarkWard]

Most likely the original rebuilder used new apply pistons and they are not included in most rebuild kits. Bentley describes how to test the assembled clutch packs with compressed air. Unfortunately you are at the mercy of the rebuilder. If new apply pistons show up, they could end up being older than yours. Sounds like the rebuilder is a bit anal which is good. The rebuild kits come with extra fiber and steel plates. You can't go by what is in there. Each assembled pack needs to be measured. Also, it is good practice to soak the fiber plates overnight in ATF prior to assembly. Enjoy the down time.
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[blackglasspirate]

Yeah, I really can't tell what's "wrong" with the old pistons because I don't have a new one to compare them to. He says they're supposed to be more flared/lipped at the end. The guy I bought the new ones from said they usually fail from getting hard and/or cracking. The one that is in the previous pic didn't have either of those problems. The seal was still soft/pliable.

Either way, I took yesterday to clean up the splines on the shaft a little more, install the 2 TC seals (National brand), and relocate the SmallCar cooler to in front of the radiator.

Now I just have to wait....

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'87 Vanagon GL Westfalia
IG: @holidayatsee
FB: https://www.facebook.com/holidayatsee