Syncro Transaxle drain plug

[FloAK]

New to me Syncro…With a transaxle plug question…

Last year we sold a 93 Eurovan in search of a Syncro. We are in Alaska, find most of our adventures in the winter or dirt road and having a 4wd makes life a bit easier. We found a Syncro that fit and just starting to tackle the ‘new to me’ maintenance and working to get it road worthy. Our goal is mechanically sound first changing fluids, etc.

Background: Most is original. Stock tin top. 207k miles. Service records show minor work mainly, also new heads, cv work. No transaxle work that we can find. Currently driving well in 2wd. Smooth-good power. At 198k in 2013, the PO removed the prop shaft due to vibration between 40-50mph. Digging through the paper work, a shop deemed the viscous coupler locked. Originally the shop replaced the prop shaft U joints, the vibration was then at all speeds, so they removed prop shaft. Shifting is responsive in all gears. There is a small chirp noise I got once when nearing 5k rpm, sounded like from underneath, hard to say mid or towards transaxle. I have driven 200 miles since purchased. Otherwise all good, drives well. Records show transaxle gear oil changed 2002 years at 160,000 miles.

Does the amount of metal on the drain plug with the background warrant looking further into the transaxle or does changing fluids and continue to drive seem reasonable?

I am starting to believe “You don’t find VW’s, they find you”, as we acquired a similar vw parts van that had an engine fire. No transmission, but a final drive with a reported good operation 20 years ago…

I appreciate wisdom that can be shared. Thank you

[MarkWard]

That’s a pretty good Christmas tree you got there. Two options. Clean the magnet and refill for now. Other choice is to open it up. Generally left to those that specialize in these. So, you’d be likely shipping it. There are known wear problems and the syncro transaxle is super rare. If you do the first option, an internal failure could get expensive.

Member Sodo will post soon. In the mean time you can search his user name for some very thorough posts. You can search 3/4 slider if you want an idea of a known week point.

Sounds like you need to address the front differential, VC, and driveshaft. Go Westy has some knowledge base regarding VC/ vs Stub. Adding a decoupler, front locker, custom driveshafts and so on. Another search item would be triple knob syncro. We sold ours. Way to many expensive rare parts that can leave you stranded. Good luck.
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[Pchill2]

What year is it?

There was some improvements to the 3-4 slider hub in late model syncros that likely would have already given out if not replaced.

The swarf present on the magnet doesn't look too alarming compared to mine and other pictures I've seen. Just be sure that there are no chunks or flakes.

Check your date stamp on the driver side of the transmission also to confirm it matches the build date (roughly) of your van.

I'm sure the experts will be chiming in shortly.
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87 Syncro Westy
Honda K24 swap

[FloAK]

[Sodo]

When you write "syncro" in the thread title, the nuts come put of the woodwork & type for hours.

Congrats on the Syncro though.
When you get it sorted, you will love it.

1988 Syncro would be european, right? Maybe it's 5.43?

See this thread Transmission Identification

198k and that magnet?
It's done.
The 160,000 mile change was likely the original factory oil, and likely showed a magnet with about that much metal too.
The bearings can't spare that much steel to the magnet.
When you see “stringy” shards (one long shard connected to the next) thats likely bearings shedding lots of surface material.

And ~40k miles may be a sensible change interval on a trans that is running clean
(like from 5k to 80k range) but its much too long on an 'old' transaxle that might be starting to shed steel.
You wanna change more often on an old gearbox to get that trash out because it creates more trash.
Like a snake eating its own tail.
Gear oil is only $30 if you can change it yourself. A bargain.
That gearbox has been grinding itself up (in it's own trash) for ~20,000 miles.

Don’t be surprised if you didn’t know this.
The rest of us had to wait ’til the info came available, so we’re all in the same boat, having ruined a gearbox or two to “learn”.
About that time we decided to learn about big engines, and bolted them to our run-out gearboxes.
But the big engines were so much fun we forgot about the ill-logic.

Does the gearbox rattle in neutral when warm?
Does the shifter move (pushing with one-finger) when you accel/decel on a steep downhill?
How far in 1st or 2nd? (Thats looseness in the pinion bearing).
How far in 3rd or 4th? (Thats looseness in the mainshaft bearing or its bore).
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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

[Wildthings]

I am going to make a wild guess that the 3-4 slider has never been replaced as the amount of swarf says the oil has been in there a long time, at least 50K miles, maybe quite a bit more. The 3-4 slider not having been replace would be reason enough to pull the box apart. Don't remember what year VW fixed the 3-4 slider problem, maybe in 1989?

[FloAK]

We are really excited! I am working on with my 15yo son. Even in 2wd + Nokian studs it goes well in winter conditions…can’t wait to get the 4wd in order…

I appreciate the replies. Here are some answers…

-I made a typo, correct year is 1987
-ID AAN2309 6

Gear box does not rattle when warm

Shifter movement….I have the van on stands not currently driving, we pulled the final drive to either replace the vc or swap to another final drive off a parts van. My memory is the shifter is relatively tight. I should have asked my questions yesterday when it was driving…can do when I get it back together…

When I got the trans ID I noticed 3 different gasket materials-looks like more work has been done than I thought originally (green paper type gasket and two different sealants). The PO said no previous trans work-they bought at 36k…but…I found a noted maintenance history….sorry for late in the post info…
-66k Trans gear oil replaced
-88k Trans replace shaft, bearing, clips, shims. Input shaft and brg 301-133
-105k R&R gearbox and rebuild, replaced main shaft bearing-seals and lube..PN if helpful.

Looks like trans oil on a better cycle than I thought…Wish there was a mention of 3/4 slider…

A pic of the different gasket materials…

[Sodo]

Does it have a rear locker?
I think most Syncros do, but some did not.
The locker "makes it happen".

[FloAK]

[Sodo]

[FloAK]

[Wildthings]

Talk to the local shop that did the work at 105K and see if they would have replaced the 3-4 slider as part of the rebuild or not. The amount of swarf you are seeing would be 100% normal if the oil wasn't changed after the 105K mile rebuild.

[MarkWard]

Your one post confused me slightly. The VC is in the “front” differential case. There are some documented VC tests posted here and I have to imagine some you tube videos how to test.

Search my gallery. Our 87 shifted fine, but had a hell of a vibration. VC test failed. Pulled the front differential and found a snapped pinion.

Working on the transmission for a crack in the reverse case section found a broken 3/4 slider. I have posted pictures of what I found.

A decoupler would be added to the rear transaxle if fitted, not a VC.

Our van ended up with the front diff and rear transaxle rebuilt, custom driveshaft and I rebuilt my VC. Ton of work and $$$. But it’s a $yncro. 😉
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[Pchill2]

You may be able to actually see the 3-4 slider hub through the oil fill hole by using a borescope. When you look through your fill plug you'll see the 4th gear mesh right in front and the 3-4 slider just to the left.

Image credit to Sodo^

The offending 3-4 slider hub has a square cut feature with small fillets at the corners. They crack at the fillet root as seen in Dan Houg's picture:

At some point they were updated to a larger fillet diameter which relieved the stress concentration slightly.

This picture was taken with a cell phone so I was unable to get a good angle on the hub. I've recently borrowed a borescope from a friend and will be inspecting next time I drain the trans.

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87 Syncro Westy
Honda K24 swap

[alaskadan]

The only syncro trans builder up here that I know of is Mike at "The Abbey" in Wasilla. He built mine and does good work. Did you end up buying that syncro body that was in fairbanks?

[RGS Paul]

Where can you get gear oil for $30? $17/L when I just checked.

Paul
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'87 Syncro 7-Pass. Adventure Touring Vehicle
"Simplicate, then add lightness." Colin Chapman

[Sodo]

I've been using Valvoline 80W-90 because it's easy to get.
Price recently increased at the FLAPS (AutoZone) from $28.99/gallon to $31.99.
It's GL5 & 'for hypoid'.
The R&P in our Vanagon gearboxes is "a hypoid gear".

===== for a Vanagon newby TL;DR for everyone else ========

I don't have any advice to offer WRT oil type/brand preferences, because I don't study oil formulations.
Oil marketing and profiteering is intense, and I can't get anything useful out of the claims.
I've never seen any concrete information that any one brand makes an actual difference.
I've seen some recommendations that specialty oils can offer perhaps a 7-11% increase in lubricity
(under a myriad of conditions which we may or may not have).
My van for example has 80% more power than OEM so even 11% is "in the noise".
Proof may exist but I have not seen it.

And the other common (VW) tale is GL5 and brass. In 40 years of Vanagon transmissions
and 40 years of GL5 there's not a single picture or proof of any attack on Vanagon yellow-metals.
Ask any Vanagon transaxle rebuilder if he's ever seen the 4th gear Syncronizer not bright yellow brass.
Pretty sure brass attack is an 'old husbands tale' WRT our Vanagon gearboxes.
Personally I'll take the higher film strength of the GL5 (for my over-engined gearbox).

That's what I'm operating on for "oil formulation" (YMMV).

Most of the racing oils offer enhanced lubricity at high temperatures (200°F ++)
but the Vanagon gearbox is limited to about 180°F
by it's wedding-cake construction, and 180°F is 'nothing' for standard gearbox oils.
We don't need high-temp benefits because the mainshaft bearing is loose below 200°F.

I'm all focused on lubricant contamination because that's what all the industry journals
say is the most significant cause of gearbox degradation, or opportunity to improve.
- and especially in an old gearbox
- and gearboxes that are over-driven.

In general, Vanagons have one or the other affliction, and many have both.

Consequently the extent of my opinion is "choose a modern ~90w hypoid" and
"don't put oil in that's too valuable to drain at the drop of a hat".
Cleaner lubricant protects gears and bearings, is your only certain option to effect longevity.
Balance the cleanliness, longevity, and the under-van-time that works for you.
Prob should drain gear oil every 2 or 3 oil-changes, if you can go under the van.
The oil base is still good, it's just contaminated by steel because your gearbox is aging.
And possibly because your electrical groundpath is 40 years old too.

Thicker oil is usually more protective, and is a general recommendation when using a bigger engine.
On my gearbox I have temperature-control, which also controls the viscosity,
so I don't use the 85-140 multi-viscosity oils.

IMHO it's much more effective to spend $100 on a transaxle temperature guage, to 'drive' below 180°F,
than spending $100 on gearbox oil that you're loathe to dump.
I don't think a 90HP can overheat a Vanagon gearboxes, unless it's old, worn out and struggling.
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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

[Bleyseng]

IMHO it's much more effective to spend $100 on a transaxle temperature guage, to 'drive' below 180°F,
than spending $100 on gearbox oil that you're loathe to dump.
I don't think a 90HP can overheat a Vanagon gearboxes, unless it's old, worn out and struggling."

I think spending $100 every other year on tranny oil changes is cheap insurance too on these "Classic" Syncro vans. Or you will be eating a $4000 to 6000 rebuild. Personally, I use Swepco 201 as I have used it in my 914 for 25 years with great results. Yes, when it's cold out it's a bit tough to shift but that goes away in a few blocks. 25 years ago 914 parts were still cheap and available but now sheesh, unobtainium. OEM Syncro parts are now getting really hard to find
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70 Ghia Black convert-9/69 build date-stock w/133k 1600 SP-barn find now with a rebuilt tranny and engine
77 Westy 2.0L w/Ljet, Camper Special engine-95hp and with LSD!(sold)
76 Porsche 914 2.1L L20c, 120hp Djet (sold)
87 Syncro Westy Titan Red 2.1L 2 knob 100k miles

[dobryan]

FWIW I have used Swepco 210, 201, and now 202. The 202 is much better on cold starts. No grinding going into second like with 201 and 210. Maybe give it a try on your next gear oil change. 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

[Sodo]

My beef with Swepco 201 and 210 is they are dyed so dark you can't see thru them.
I like to let (reasonably fresh) used gear oil sit in a water-clear jug on a shelf for some months, look at the stuff fallen to the bottom.

And pour off the purified oil from the top.
Knowing it's hella cleaner than it was 6 months ago.
Possibly settled longer thus even cleaner than when it came from the store.

Of course you can still pour off the clean oil with Swepco too.
In 6 months it's firkin' PURE like any other oil,
but it's just a little more satisfying when the oil is clear like honey.

Swepco makes no bones about their target market protecting old, over-driven gearboxes.
Swepco is probably a good bet for choosing a $100 brand.

I talked to the Swepco engineer once, he said for over-driven eqpt, thicker oil is your only hope. He said for doubling the HP you want to use 210 or 202. And temperature thins oil so either you start thicker or use multi-viscosity.
He also said that you can only expect "so much" from a chemical solution when what your application needs is bigger gears and bigger bearings.
He said that contamination by steel is the inevitable result of overdriving a small gearbox and that you have to get that contamination out if you have hopes for longevity.

I've never used 202.
It's probably good stuff.
Is it dyed dark?
It's not too expensive if you gravity-purify it.

I have a brand new gearbox with about 5k on it.
Also have an on-board oilpump that can replace the gear oil at the drop of a hat.
$30 oil gets real real cheap when it's sitting on your shelf.
I guess $100 oil would be cheap too, purified.

I could start it on Swepco 202.
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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