Larry,
Also poppycock! I just rebuilt my OD on the '65. It has 200,000 miles
on it, the last 50,000 miles with MTL. The linings were perfect, as was
operation of the unit over its entire life, and the OD is used virtually
every day. The reason for the rebuild (in addition to its age) was a
noisy thrust bearing, every other part was serviceable, but I put in all
new bearings and O-rings anyway, of course.
Lining wear occurs primarily on the outer lining (the unidirectional
clutch locks the sliding member (and its friction surface) to the
annulus when going forward with the OD disengaged), and is caused by
inadequate hydraulic pressure that allows slippage. This is due to
problems with the pump, o-rings, dirt, wrong fluid, etc., not Red Line.
The tranny had 100,000 miles since I last rebuilt it, and its last 50k
were, of course, also with MTL. The bearings were perfect, and only the
3rd gear syncro showed any wear at all, and that was just a slight wear
on the engagement tangs. Unfortunately, this unit had only a single
needle bearing in the first gear end of the laygear, and that had
severely worn the shaft and the laygear to a lesser extent. There was
minimal wear on the 3rd gear end, which had two bearings. I had a
machine shop hone out room for a second bearing on the weak end and
expect this gear to go at least another 100,000 miles.
Racing is extremely hard on any gear box, and no oil is going to
completely protect it. The brass syncros and shift forks will take
severe stresses, as will everything else. There is simply no way you
can blame Red Line for actually causing a gearbox failure.
One of the the weakest parts of these boxes is the laygear/layshaft, and
even Red Line can't help that design defect, especially if you race. If
I were preparing one of these boxes for racing I would have the laygear
bored or honed out to a uniform diameter all the way through and pack it
with as many caged needle bearings as would fit. A slightly simpler
approach would be to hone out enough room on each end for three
bearings, and pack six sets of loose needles in each end to increase the
bearing surface, cutting down the spacer and separating with snap rings
accordingly. Loose needles are a PITA, but with enough thick grease it
can be done. Or you can use caged bearings.
My experience with MTL shows it to be an excellent product for the MGB
OD transmission, and I didn't make this decision blindly. After seeing
Red Line sold at my local Volvo dealership (it used to be an MG/Volvo
dealership and they had NOS MGB stuff) years ago I asked the parts man
about it, and he said they recommended it for their transmissions. When
I commented that I thought it would be bad for my MGB OD, he said they
use it in their OD's which are also made by Laycock. (look familiar?
http://www.volvocars.com/parts/moz1/overdrive.shtml)
Been using it ever since!
Modern products can benefit our old cars. The other new product I use
exclusively now is long life coolant, the orange stuff, from Prestone or
Havoline Dexcool. But that is another topic!
Larry Hoy wrote:
>
> Stuart, slow down. MTL is too slippery. In the Laycock OD the power is
> transmitted through a friction material, the MTL causes slippage, which causes
> premature wear.
>
> Larry Hoy
>
> >-----Original Message-----
> >From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net]On
> >Behalf Of Stuart MacMillan
> >Sent: Monday, July 17, 2000 7:44 PM
> >To: WSpohn4@aol.com
> >Cc: mgs@autox.team.net
> >Subject: Re: OD Lube
> >
> >
> >Poppycock!! You can't blame Red Line for a failed transmission,
> >something else was wrong with that box, perhaps even its basic design.
> >If you want a heavier oil use Red Line MT-90 for racing.
> >
> >High quality synthetic oils are much more consistent in composition than
> >mineral oils, and have a higher percentage of the good long molecular
> >chains that provide superior lubrication. Combine that with an equally
> >high quality additive package and you cannot do better. I'll never use
> >anything else in my gearboxes, no matter what the application!
> >
> >WSpohn4@aol.com wrote:
> >>
> >> In a message dated 17/07/00 3:50:09 PM Pacific Daylight Time,
> >> owner-mgs-digest@autox.team.net writes:
> >>
> >> > You won't regret the conversion, all four of mine have or will have OD.
> >> > Also, I highly recommend Red Line MTL synthetic oil for these boxes, a
> >> > far better lubricant for the pressures in a transmission than motor
> >> > oil. MTL stands for manual transmission lubricant, and is offers easier
> >> > shifting as well as improved longevity. Excellent for the syncros and
> >> > won't harm the OD.
> >>
> >> Unless you race! In which case it can trash it within 30 minutes! Beware.
> >>
> >> Bill Spohn
> >
> >--
> >Stuart MacMillan
> >Seattle
> >
> >'84 Vanagon Westy (Escape vehicle)
> >'65 MGB (Daily driver since 1969)
> >'74 MGB GT (Undergoing restoration)
> >
> >Assisting in restoration:
> >'72 MGB GT (Daughter)
> >'64 MGB (Son)
> >
> >Parts cars:
> >'68 & 73 MGB, '67 MGB GT
--
Stuart MacMillan
Seattle
'84 Vanagon Westfalia
'65 MGB (Driven since 1969)
'74 MGB GT (Restoring)
Assisting on Restoration:
'72 MGB GT (Daughter's)
'64 MGB (Son's)
Parts cars:
'68 & '73 MGB, '67 MGB GT
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