MTL and MT-90 are not for use in transaxles or differentials with hypoid
gears, which means not for use in VW transaxles. Redline says, not for
use with hypoid gears, right on their website. I love these products and
all the Brit and Jap cars I built got them, but I wouldn't use them in a
VW transaxle. In addition, the MTL is way too light for a transaxle even
if it were suitable for use with a hypoid gear. To get the same friction
modifiers in a Redline product, I'd go with Lightweight Shockproof -
Film thickness greater than an SAE 75W140, yet low fluid friction like
80W gear oil. And it has the right mix of friction modifiers for a
manual transmission in most cases. If this doesn't work for a specific
application, I'd go with the 75W90NS. Shockproof is amazing stuff and
offers a very high level of protection without the drag of a thick oil.

Here's an interesting thread on transaxle lubricants.
http://www.thesamba.com/vw/forum/archive/index.php/o-t--t-366486--.html
> MT-90 is a 75W90 gear oil (viscosity about the same as a 15W40 motor
> oil). Redline MTL is thinner, a 75W80W. Are you sure you weren't using
> the MTL?
>
> You don't say which Swepco product you used. I think the Porsche folks
> mostly use their 201, which is available in multiple grades, up to a
> 250! Their 210 is an 80W-140, which sounds closer to what you describe.
>

--

Marc Sayer
Journalist, Photographer, Dog Trainer (APDT member #062956)
Board member - Western States Great Dane Rescue Association
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Oakridge, OR USA

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