Re: Sudden loss of AT Fluid

[Kim Sol <kimsol@domain.elided>]

Rob was way low on AT Fluid in IH Digest V5, #110, for no real obvious
explanation other than normal leaks, but it seemed to occur suddenly. An
observation:  IH made two modifications to the Torqueflites: IH used one
of its own output shafts, requiring a special output shaft bearing,
which is no longer commercially available except by special manufacture,
by the same guys that make Navy hammers (ie $500 or so JUST FOR THE
BEARING).This is the biggest and most expensive headache of overhauling
an "IH" Torqueflite.  Fortunately, the original bearings are extremely
tough, and need replacing after only exceptional abuse, or several
overhauls.   The other modification was to connect the transmission to
the engine vaccum to modify the second gear shifting.  So, on the left
side of the tranny there is a vacuum control unit input that has a
gasket or O-ring.  That gasket is pressurized only as the transmission
passes through second gear. Otherwise, the gasket is not in contact with
pressurized transmission fluid.  So, if the Scout is in slow traffic,
and doing a lot of second gear running, a failed gasket or switch will
gush fluid, but as soon as the Scout gets to highway speeds, its just
fine; similarly, while it is sitting in the driveway, or idling, there
will be no telltale fluids, either. So, you don't ever see much fluid
laying around, except a telltale wind smear down the inside of the left
frame rail, you just run out of AT fluid. If your second gear sees
little use each day, the effect is fairly negligble except after a few
weeks or even months; if you are caught in a lot of 25 mph zones, or
4wheeling, you might be in trouble fast. The local Torqueflite
specialist here says that he's never seen any other Torqueflites with
this second gear feature except Scouts, and he's not sure what the point
was. The replacement switch is apparently out of production, however
(since it was not a Chrysler part), and so he just puts in a metal plug
to replace the switch and gasket, and it does not seem to appreciably or
even noticeably affect the operation of second gear, but definitely
eliminates the mysterious disappearance of AT fluid.  Kim Sol, '80 Scout
II, '76 Scout II, '72 Scout II (all automatics).