gears
Samba Member
Joined: October 28, 2002
Posts: 4411
Location: Tamarack, Bend, Kailua
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 Posted: Wed May 01, 2024 2:02 pm Post subject: Trans oils & synchros |
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After decades of recommending Swepco (and a couple other) oils, I am now 100% convinced that the BG Ultra-Guard recommended by German Transaxle is superior to ALL other gear oils, mineral or synthetic. I have replaced (under implied warranty) a number of mainshafts exhibiting "oil-related issues" (resembling heat-treatment issues), yet GTA, who installs probably 10X the number of GT mainshafts as all other US shops combined, has never had a comeback of this type.
While most of us are going to be more conservative than this, GTA doesn't push a 500-1,000 mile break-in oil change, and instead recommends their customer's first oil change at 5K, and the second oil change @ 15K.
Regarding synchro rings, GTA uses brass synchros on 1st & 4th gears, and moly-coated on 2nd & 3rd gears. This combination has proven best for them performance-wise with the BG Ultra-Guard. (You must NOT replace a moly synchro with a brass synchro during a rebuild .. another story.) Shifting has always been somewhat baulky for me with Swepco.
My gear cutter, who has 1000X the experience with performance gear sets that I have, has seen SO many oil company shenanigans, that for decades there were NO synthetic gear oils he would recommend. I sent BG's spec sheet to him, and he liked what he saw, at least on paper. I am now going to recommend that he source BG for ALL his race customers, regardless of the cost (outside the US).
While GTA uses one specific BG product for VW street transaxles (#750), there are two other versions that we will also be utilizing in the future .. one with LSD additive, and another 75/140 version for track use.
In the meantime, GT is moving toward a specific tooth design for all future gears that our manufacturer claims will tolerate even the lowest quality gear oil that someone might use.
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com |
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DanHoug
Samba Member
Joined: December 05, 2016
Posts: 5688
Location: Bemidji, MN
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| Posted: Wed May 01, 2024 3:02 pm Post subject: Re: Trans oils & synchros |
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okay. i'm down with this being settled! BG UG 750 it is!! thanks for the input and corroboration with GTA. between your parts and the experience of GTA, i'm satisfied.
i *just* bought another jug of Swepco 202 and since mine shifts perfectly with it for the last 20k miles, i'll keep using that on this transaxle. on my NEXT one, i'll use #750
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-dan
60% of what you find on the internet is wrong, including this post.
'87 Westy & '89 Westy both 2.1 4spd
Past projects can be found at--
www.thefixitworkshop.com |
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