Transaxle Sudden Death Syndrome. Really?

[E1]

[kamzcab86]

[DuncanS]

Happened to me twice towing a 17' Boston Whaler and motor with pre '91 3/4 sliders. Neither had any warning. Car ran fine with no trouble shifting or odd tranny noises and then it was in both 2nd and 3rd gear at the same time. Gearshift lever was frozen.

Duncan

[LarsHepping]

[Sodo]

[DuncanS]

[ZsZ]

BTW you guys have cheap parts through Weddle.
Gearbox parts are OEM priced this side of the pond.
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Zoltan
1.9 MTdi 2wd Multivan (ex Caravelle)
Van since 2006, engine since 2008

[Sodo]

Weddle’s focus is racing. Their gears are tougher, built to finish the race.
Not the long haul.
But you have to replace them every few seasons.

GTGears are built for longevity, but they’re more expensive too.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[E1]

[bobbyblack]

E1

Well, if you start your morning off thinking thoughts like this, you'll have your answer

https://www.thesamba.com/vw/gallery/pix/2456965.jpg
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'87 Westy 'Flossie','86 Westy 'R1','86 tintop GL - Subi2.2 'J2','83.5 stock tintop L 'ZoomBus','74 Karmann Ghia, '63 Notch

[ThinkingD]

Californio: Difficulty shifting between 3rd and 4th still drove fine, when in gear until it failed and stuck in 3rd.

Skills: it was a 5k (Can) rebuild with a solid list of new parts and pictures. Work was coordinated through Eurotech Motors in Almonte ON.
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87 Titian Red Westfalia 2.0 VW I4 SOHC manual Ottawa, Ontario

[skills@eurocarsplus]

[Sodo]

[Howesight]

Adding on to Sodo's comments above, the Weddle gears that many of us use to get our preferred 3rd gear and/or 4th gear ratios are designed to absorb abuse, and also meet a certain price point. The metallurgy is very good, and the toughness of the alloy that racers want in order to avoid gear breakage does not permit the surface hardness that we Westfalia drivers want in order to maximize gear life. Weddle tries to address this with case-hardening, which helps the teeth to last somewhat longer. But eventually, the case hardening pops off (called "spalling") and we get swarf and from that point, accelerating wear on these gears. Sand buggies, by contrast, don't drive to Patagonia.

The solutions include a more advan$ed alloy, and more preci$e hobbing of a better tooth de$ign. That is what Guard Transaxle (Paul Guard, aka "Gears") has kindly done for our little Vanagon community. De$pite my clever $pelling in this post, I strongly suspect that Paul and his manufacturer are selling their products almost at cost, which you can easily see by looking at how much more Albins is charging for similar technology that is not made for the lowly Vanagon.

Thanks, Gears, for solving a lot of the problems that we over-engined folks have created for ourselves.

Full disclosure: Our Synro SVX combo features Weddle 3rd and 4th gears and some of their other parts. In 2012, when that transaxle was rebuilt by Darryl Christiansen (RIP), there were no GT Gears products for our transaxles. When it's time for a rebuild, I think I will DIY and I know I will use GT Gears.
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'86 Syncro Westy SVX

[riceye]

I have a question!

Speaking statistically, is the 3-4 slider failure more a function of mileage on the transmission (assuming it has the older parts with the square cuts that are proven vulnerable) or is it a function of the number of gear shift cycles?

I ask because during the ownership of our Westy, dating back to 1994, the vast majority of the miles have been getting us from the midwest to the Rockies and beyond in as short a time as possible. In this scenario it is very possible that 1000 - 1500 miles were logged with less than twenty shifts from third to fourth, and vice versa. The only stops are to gas up (every 200+ miles or so) or to bivouac in a rest area.

Let's describe this as a low shift/mile ratio.

When we do get west, and in "vacation touring mode" we certainly do drive less miles with more shifts, but even then it is less shifting than my 12 month grocery getter (2000 4Runner with a five speed) sees. I may shift from third to fourth and vise versa several times in one mile. A high shift/mile ratio.

So, do the vulnerable parts suffer more from mileage or from the number of shifts, all else being equal?
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'87 Westy Weekender - daily driver on salt-free roads

There's gonna be some changes made.

“I find that things usually go well right up until the moment they don't.” - Ahwahnee

"Quality isn't method. It's the goal toward which the method is aimed." - Socrates, later quoted by R.M. Pirsig

[E1]

Riceye, great question.

Just to me, very subjective (!), here’s the worst wear points:
— Heat
— Old oil
— Wrong oil
— Full torque
— Anything but a buttery shift into a next gear, the harder the engagement the worse the wear (Obviously, gear-grinding!)
— Any downshift that changes rpm when the clutch comes out, the higher the rev difference, the worse the strain — biggest loser being the clutch
— Hard and fast on-throttle to off-throttle, and inversely

Rough-housing on dirt is harder than same on pavement, but high-speed runs at full-hot and especially on thinner oil and dare I say non-synthetic oil, I think, may be the worst of all just in sheer hard time spent at full-hot. Our van loves 55, puts up with 65 if gentle, hates 75, mechanically, pretty quickly.

Genuinely interested in others’ take on this…
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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

[E1]

[riceye]

[E1]

Yes, my bad and sorry to be so general.

I think this warrants a dedicated thread, to be honest. Very subjective and interesting… my first thought would be “shift cycles” for sure, but there’s questions of heat and oiling and operational speed that makes it more interesting yet… in terms of what parts are being worn, their place in the system, and their durability.

And addressing speed, my comments are general in terms of weight being a huge factor. An empty van at 4,000 lbs. is obviously at far less stress in general than a fully-loaded Westy at 5,500 (we’re just over 5).

Go, Packers.
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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

[IdahoDoug]

The 3/4 slider on my Syncro let go in the 150k range after a life of care by an experienced older stickshift driver who bought it new and cared well for it. Never offroaded. I got it from him and similarly kept stock tires on it and drove it respectfully - also never had the chance to offroad it.

The shifter jammed one day randomly and I crawled home in 2nd with the flashers on.

I bought parts from Weddle and other vendors, pulled the transaxle apart, and totally rebuilt it in my garage. Heavier gear case, S. African oiling bits, locking tab and stainless reinforcement on the main bearing, etc.

My assessment on the failure was as others have noted. The slider had sharp corners, versus the later sliders which were properly machined with a curve to prevent stress cracks.

I don't think it possible to differentiate between a slider failing from shift quantity, or heat, or abuse. Or the general wear to other parts which might be creating angular force on the 3/4 slider as slack develops elsewhere. As a former Powertrain Planner for GM, if a part is not properly engineered, it will fail from any or all of these contributors.

This is a frustrating fail, but the good news is when it fails, I'm not aware of instances of the entire gearbox getting instantly trashed - it's fairly benign. You just suddenly can't get 3/4 very well or at all. And if you know about it from discussions here and other websites (as did I that day), you won't angrily try to jam it into 3rd and destroy something. Instead, you'll hang your head for a second, then safely get the Van home to be worked on. So the constant discussion of it is an overall good thing, IMO.
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1987 2WD Wolfsburg Vanagon Weekender "Mango", two fully locked 80 Series LandCruisers. 2017 Subaru Outback boxer. 1990 Audi 90 Quattro 20V with rear locking differential, 1990 burgundy parts Vanagon. 1984 Porsche 944, 1988 Toyota Supra 5 speed targa, 2002 BMW 325iX, 1982 Toyota Sunrader