I think I need a transmission rebuild

[zoti]

I have a 1988 2WD manual transmission.

I have a whine going from 2nd to 3rd and down from 4th to 3rd.

Other than that everything is fine. No grinding, no noises when in 3rd or 4th.

I'm thinking about rebuilding it. I have an auto shop but I don't have experience building transmissions.

Can it be done DIY style?

I'm thinking of adding a diff locker as well as fixing the 3-4 hub. Anything else? Maybe a longer 4th?

[MarkWard]

Yes, with mechanical skills you can go through the later 4 speed. You should have the factory manual and there are 3 tools you can purchase that would be hard to fabricate. Everything else can be done with simple tools. I am using the shop BBQ grill for heating the case. Shipping to a rebuilder 2 ways is more than the cost of the special tools. It’s fair to be cautious. I worked at a Porsche Audi dealer for 5 years. I would tackle anything even if I lost time. I remember Porsche techs refusing to do transaxles. I guess they thought they were full of spiders and snakes. Given a choice, I’d rather build manual transaxles and transmissions over engines. No surprises. I vote go for it.
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[Howesight]

Zoti, if anyone can do a DIY rebuild, it's you.

Obviously, you have a press. You need a few specialty tools, some that can easily be fabricated. Have a look at the Samba's Andybees transaxle rebuild and also, for great pics, the thread done some years ago by JPATE, who rebuilt his 2WD transaxle the luxury way - - with all the correct VW and Kukko tools. You won't need to buy all those tools, as mentioned above, but it's nice to see how the factory-recommended tools work and fit so that you can fabricate some of them.

I have not built one of these transaxles, but did build and rebuild Type 1 transaxles many years ago. (I made my shift-fork jig out of an old Type 1 transaxle case that I cut up.) I plan to rebuild my 094 when it needs its next rebuild - - mainly for the experience.
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'86 Syncro Westy SVX

[E1]

[MarkWard]

Disclaimer: I like buying and owning tools. The side cover tool I’ve seen made. I’m sure they work fine in some instances. But if you are changing the differential or ring and pinion. You can spend a good part of a day taking the side covers off and on setting pinion depth, differential bearing preload and backlash. The actual tool works. The large pinion nut tool is pretty unique. You may find that you have the ring and pinion in and out as many as 7 times getting it right. That tool also works. The tool for securing the 1st gear pinion nut race would be hard to replicate and it too works.

I fabricated a tool to keep the case from spreading. Without it, I don’t think you can get the differential bearing preload and back lash repeatable. I posted a picture of my case tool.

I purchased a complete set of pinion shims and honed a spare large pinion bearing so I could easily remove the pinion during setup. I did upgrade to a Peloquin differential. It was slightly wider than stock, so I was not able to use the original marks I made in the side covers. I’m talking thousandths though. Weddle and GT gears are the suppliers I used. It adds up quick, but the parts are available. Ring and Pinion ratios are specific to the owner, power plant, tire size and the mph you operate at mostly. I’m sure the short ratio Ed is running works for him. It may not be for you. Knowing your power band, tire diameter, preferred cruising speed the math will tell you what gearing is best. Taller is not always better.

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[AndyBees]

Tools, tools, etc., as well as some unconventional techniques with some of the procedures is for the DIY guy.

This is one of many ways to make a tool to remove the side adjusters. It is a disk with nuts welded to engage the adjuster. In the second photo you can see the square piece of tube welded to the back. It works well with a bar through the hole or a pipe wrench when necessary. Of course, you need a side adjuster as a jig to do the fabricating.

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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.

[dobryan]

^^^^^ Andy yikes that case was crusty!!!
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[danfromsyr]

there's several videos on u-tub
and while this is for a 002 Bay trans, here's a great overview of the process
https://www.smbaker.com/002-vw-transaxle-rebuild
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[dobryan]

Careful on changing gearing.

I have tried different combos and am now back to stock. The stock gears also likely will last longer than any of the aftermarket gears.

I now change 'ratios' by tire sizes. My current is 215/75/15 which is about 7% taller than stock.

YMMV.
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[E1]

Zoti, Mark is dead on target assuming I’m the “Ed” he mentioned.

When you said “locker,” I’m thinking you’re doing a more offroad setup — which makes me think you’re likely running bigger wheels and tires as well. My comments presumed that… but I jumped the gun.

Our tires are 27” high, on 16s. A 5.43 R&P change needs those or would be *too* revvy and early-shifting — and it needs a new 4th so it’s at normal or a little less rpm than stock at highway speeds.

The advantage is 1st through 3rd revs much, *much* easier instead of lugging those tall tires. The tires add about 6% in height but the ring takes that away — plus another 6%, if that makes sense. Throttle response is *markedly better* everywhere, and in all conditions, in 1st through 3rd.

The only highway downside is 3rd needs shifting to 4th at about 5 mph slower, like if wanting to make a pass at 55 or so. But in real terms, after seven years with this ring change on two vans over 65,000 miles, and that we rarely pass in tight quarters anyway, it doesn’t really matter.

With so little power, the gains are extraordinary in having more revs to deal with slow to slower hills on paved (like using 3rd in the 40-50 mph range where it’d normally need 2nd at 35), and in pulling 2nd where you otherwise need 1st on dirt. In my opinion, that right there makes dirt much easier in engine strain and temperatures, gearbox strain and temps, the lot — plus is a much more fun and comfortable drive. We’re almost never in 1st on even rough dirt anymore.

A TBD also *loves* the ability to grip with more or easier revving — as does the clutch, and especially if one’s foolish enough to get stuck! (according to a friend ).

Hope that clarifies a little. And most or all of what I’m saying also presumes you have a stock Wasserboxer.
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‘84 Westy, 2.1L with Digijet, 5.43 R+P, GT Gears
"Adding power makes you faster on the straights.
Subtracting weight makes you faster everywhere."
— Colin Chapman

[Sodo]

[zoti]

[E1]

Same wheels and tires here.

All I’ll add is we bought our second van with 14s, put the 16s on within a few hundred miles, and was shocked what a stone we had for the next three years.

Added the 5.43 when rebuilt in 2021, felt like we were “back home” like our prior van (with a 5.43) and gained a ton more torque and acceleration and functionality.

I’m again presuming you have a Wasserboxer…
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‘84 Westy, 2.1L with Digijet, 5.43 R+P, GT Gears
"Adding power makes you faster on the straights.
Subtracting weight makes you faster everywhere."
— Colin Chapman

[MarkWard]

Tom, I am securing the case to keep it from spreading while adjusting the side covers. The case is too flexible with out the bell housing to get repeat measurements.

So, I set the differential bearing preload with the case secured. Once I have that set, I mark the side covers for reference as I move on. Pinion depth and back lash go hand in hand. So everytime you try a new pinion shim, you have to reset the backlash. I was chasing my tail for a good part of the day without the fixture.

Once I had the depth and backlash set, I remarked the side covers for their new position. I then backed off one ring about a 1/4 turn. I installed the bellhousing torqued on final assembly and then spun the side cover back to my new mark. Since I used the fixture, I knew alignining my marks with the bellhousing installed would replicate backlash and preload.

I'm a bit anal and like repeatable measurements. For the person just refreshing bearings, you likely could get away with using your orginal side cover marks and remeasuring the backlash you noted down on disassembly. In my situation as I mentioned, I was installing a new ring and pinion set as well as going from an open differential to the Peloquin. While tedious, I do enjoy the task of getting it right.
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[danfromsyr]

Weddle has an exploded view booklet on PDF
https://weddleindustries.com/sites/weddleindustries.com/files/downloads/VW-VAN-2WD-EXP-VIEWS.pdf

located in Weddle's downloads library
https://weddleindustries.com/downloads
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[MarkWard]

[zerotofifty]

[zoti]

[zoti]

Has anyone ever tried looking into the transmission with a scope camera to see the hub? I wonder if it is possible.

[AndyBees]