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Re: Slipping O/D

To: A666K@aol.com, spitfires@autox.team.net
Subject: Re: Slipping O/D
From: "Dean Dashwood" <Dean.Dashwood@enron.com>
Date: Mon, 31 Jul 2000 09:32:54 +0100


Avi, overdrive is not supposed to be enabled in 2nd gear at all - not only is it
not designed to take the high torque of lower gears, but I believe that there
isn't enough oil pressure in the gearbox at the kind of speeds you'll see in 2nd
gear to engage it properly - that's probably the reason you're seeing it
slipping.

There should be an "inhibitor switch" mounted on the top of the gearbox, towards
the front.  This is a normally-opened switch which becomes closed when in 3rd or
4th gears (actuated by a lobe on the gear shift mechanism).

The correct wiring sequence is: 12V in (from somewhere under the bonnet).
Connects to one side of the inhibitor switch.  (Also splits here to provide a
feed for the reverse light.)  Other side of the inhibitor switch connects to the
switch in the gearstick.  Other side of this switch goes to the overdrive
solenoid, and the other side of this is grounded through the gearbox body.


While we're on the subject:  My overdrive has become intermitent in 4th gear.  I
replaced the inhibitor switch a few months ago, and it was fine for about 2
months then the same problem began happening again.  There are no spacers or
gaskets between the inhibitor switch and the gearbox that I can remove.  Anyone
know a solution for this which doesn't involve taking the gearbox apart?  I have
the tunnel out at the moment, and would like to fix this while it's out.
Otherwise, I may consider bypassing the inhibitor switch.

Cheers,

Dean
----------------




Date: Fri, 28 Jul 2000 04:09:28 EDT
From: A666K@aol.com
Subject: Slipping O/D

Hey all,
The other day I noticed the O/D slips under hard accel. in 2nd, especially
when colder. I recently put in RedLine MT-90 fluid, and suspect that is the
problem. Checked the archives and saw a survey done on O/D fluids, but
couldn't find a conclusion (Joe?). There was mention about fluids causing
slipping though. A friend with a Jtype O/D but in a TR6 claims slipping using
of Hypoid 90 gear oil. Any recommendations in general? Anybody else using a
RedLine product in a Jtype O/D?
TIA,
Avi



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