| Learning about the Jetaway Transmission
Automatic Transmissions was a course I had at Dunwoody and Mr. Jenson
(the instructor) used the Dual Coupling 4 speed Jetaway to teach the course.
He stated that this trany used every type of clutch used in other units
so it made sense to go with it. Oldsmobile had been experimenting with the
automatic transmission since the thirties and General Motors relied on that
division to develop a unit for the other car lines. My 55 Oldsmobile had
a Dual Range automatic of which I never had the opportunity to take apart.
A opportunity to rebuild one.
Thirty years after Mister Jenson's class, I got to rebuild a Jetaway
in a fifty seven Olds at the Grand Canyon. One of the park employees had
this gray and white Olds (just like the one I had) stored in their trailer
house driveway for several years. By then word was established in the community
that I did automatics down at the Public Garage. The folks saved enough
bucks to get it repaired as the trany had been out several years I got it
all torn down and cleaned up to see what parts were needed. Knowing that
nobody local stocks stuff like this anymore, I found a place called "Fatsco
Transmission" in New Jersey. I got it together in a day after the parts
showed up and could hardly wait to road test the car. In Drive position,
the unit starts out in low gear ( very low ratio) and up shifts about five
miles an hour. With moderate throttle pressure, second gears holds in there
to about thirty five. Third gear has an interesting event take place as
it slowly slides into engagement. A large internal fluid coupling must fill
with oil to drive a planetary member to make third gear. Fourth gear occurs
without a noticeable event. My rebuild job did every thing as expected,
so I called the customer and said' " pick it up, it's ready to go".
Why the thirty year wait?
After finishing school, I worked only for Chevrolet dealers (besides
auto electric work) there were Power Glides, Turbo 350's, 375's, 400's and
425's to rebuild. The Jetaway gave out to Slim Jim's soon in Olds and by
then the old Dual Couplings were in the junk yards because the cars rusted
out quickly in the Midwest.
The next car was a 1965 Cadillac Coup DeVille rag top. |