Syncro Transaxle

Discuss VW transaxles and transmissions. Gearheads wanted!

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Pablo2
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Syncro Transaxle

Post by Pablo2 » Thu Feb 07, 2013 11:51 am

Since this forum is slow, here's a link to a Syncro trans thread:
http://www.thesamba.com/vw/forum/viewto ... le+service
aka Pablo, gears, Geary
9.36 @ 146 in '86

Dougy Dee
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Re: Syncro Transaxle

Post by Dougy Dee » Fri Feb 08, 2013 10:05 am

Wow!

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fusername
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Re: Syncro Transaxle

Post by fusername » Sat Feb 09, 2013 12:38 am

wow. further proof that when I open a trans to rebuild, I will have 0 idea what wear looks like. Ugh i hate not knowing. good stuff, bookmarked.
give a man a watch and he'll allways know what time it is. give him two and he can never be sure again.

Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.

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Henryhoehandle
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Re: Syncro Transaxle

Post by Henryhoehandle » Sat Feb 16, 2013 6:42 pm

Why didn't you loctite the pinion bearing nut? BTW your camera rocks!

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Pablo2
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Re: Syncro Transaxle

Post by Pablo2 » Sun Feb 17, 2013 6:53 pm

The harder Chromoly can present seizure issues that the soft OE nut never had. This is because the pinion bearing and aftermarket nut are close in Rockwell hardness.

I wished to convey my hesitancy to use Loctite (which can increase risk of thread seizure), while promoting an alternative (race-tested) method of securing the Chromoly lock ring.

The bonus is that this method allows using lubricating oil on the threads, rather than Loctite.

I also wished to point out the superiority of the Type II nut over the Type I nut .. a no-brainer in all Waterboxers.
aka Pablo, gears, Geary
9.36 @ 146 in '86

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Henryhoehandle
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Re: Syncro Transaxle

Post by Henryhoehandle » Mon Feb 18, 2013 6:17 am

Makes sense... I haven't had trouble with loctite seizing on the threads, but it does make it a pain to get the nut off if the bearing starts spinning in the case. A stock T2 nut will hold a lot and I have seen very few actually pull the threads from pinion force.

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Pablo2
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Re: Syncro Transaxle

Post by Pablo2 » Mon Feb 18, 2013 9:45 am

It's normally off-road shockloading that causes the stock nut to expand and jump one thread. It doesn't take long to loosen further, allowing the pinion bearing to slop forward/rearward in its bore.

The stock nut in a Type II is the same as in a Type I .. thin and inadequate for some applications. The Chromoly version Type II is much thicker as it incorporates the washer .. and it has one or two more threads.
aka Pablo, gears, Geary
9.36 @ 146 in '86

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Henryhoehandle
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Re: Syncro Transaxle

Post by Henryhoehandle » Mon Feb 18, 2013 10:22 am

The chromoly one with the washer is the one I use for hp use.

Bruce2
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Re: Syncro Transaxle

Post by Bruce2 » Mon Feb 18, 2013 12:51 pm

Henryhoehandle wrote:.... it does make it a pain to get the nut off if the bearing starts spinning in the case.
That's why I never use loctite on the nut.
I find many cores I pull apart have a loose nut. But that same loose nut was staked by the factory. My conclusion is that the width of the bearing support part of the case got pounded over time.

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Pablo2
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Re: Syncro Transaxle

Post by Pablo2 » Sat Aug 31, 2013 9:14 pm

Here's the latest installment on Syncro transaxle upgrades, from sister forum:

http://www.thesamba.com/vw/forum/viewtopic.php?t=568039
aka Pablo, gears, Geary
9.36 @ 146 in '86

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Pablo2
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Re: Syncro Transaxle

Post by Pablo2 » Sun Jun 10, 2018 10:55 am

I thought I'd update this thread, showing the parts we're now offering to build the ultimate-strength Syncro 4WD Vanagon transaxle ..

Gears with F1 tooth profiles (German steel, ultra-deep heat treatment):
Image

Gun-drilled mainshafts supply oiling to all needle bearings (note replaceable 2nd gear synchro teeth):
Image

Besides greatly increased strength & longevity, this new carrier offers integral splash plates/dams and a secondary thrust bearing for the pinion:
Image
aka Pablo, gears, Geary
9.36 @ 146 in '86

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