Date: Tue, 28 Aug 2012 19:00:14 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Gear box oil - Redline MT90 or Swepco ?
In-Reply-To: <656BFBA7-FBB9-4B67-8E7B-96DB1BF6EC80@comcast.net>
Content-Type: text/plain; charset="US-ASCII"
From the factory, except for 1st gear the wear surfaces of all the
synchronizers are molybdenum coated.
During rebuilds only the economy syncros are not coated.
I have yet to see any issues of corrosion except for trannies parked for a
real long time in a real bad place. Or once enough corroision has formed on
top of the box for there to be a hole!
Syncro rings are cheap! Ring and pinion sets and some gears are not. I want
the most extreme pressure protection I can get. GL-5 for me!
The main reason for the GL-4 spec is that GL-5 may be too slippery for the
Syncro rings to "grab" So who power speed shifts their Vanagon?
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
OlRivrRat
Sent: Tuesday, August 28, 2012 12:27 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Gear box oil - Redline MT90 or Swepco ?
Some interesting info here ~ scroll down to list of 22
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2556
125
Nice image here that shows the CopperStripTest classifications
http://www.machinerylubrication.com/Read/28958/ep-additives-effects
On 28 Aug , 2012, at 1:10 AM, Gene P wrote:
> [clip clip, lots of folks wrote]
>
> Very confusing issue and discussion. Just a few brief points:
> 1) The German mechanic that installed a rebuilt transaxle for me 9
> years ago said "use GL-4 oil only, NOT GL-4/GL-5, GL-4 ONLY. Wrote it
> that way on the invoice.
> 2) GoWesty is not everyone's reference of choice, but they still
> recommend and sell MT-90.
> 3) The Redline website has an application guide: plug in your vehicle
> (for me an 87 2.1 hardhat) and the recommended transaxle oil is MT-90.
> 4) Following a discussion like this about 6 months ago, I called
> Redline and the person I talked to knew nothing about a formulation
> change and could not imagine why one of their reps would say MT-90 is
> not recommended for our vehicles. When I asked about the "not for
> hypoid differentials" statement on the site, he said Hypoid
> Differentials are not the same as our Hypoid Transaxles and went into
> some stuff about shaft angles and pressures and whatever that was way
> over my head.
> 5) A clip from a dandy 2-page technical article on Redline's
> website:
> "GL-5 gears oils which are required in hypoid differentials are
> not used in most synchromesh transmissions because the chemicals used
> to provide the extreme pressure protection can be corrosive to
> synchronizers, which are commonly made of brass or bronze. Typically,
> the use of a GL-5 lubricant in a synchromesh transmission will shorten
> the synchronizer life by one half."
>
> So ... I ain't an expert, but I did enough homework to be comfortable
> continuing to use MT-90 and to throw out a caution about any GL-5.
>
> Your wives' tales may vary ...