After being totally frustrated with the stock programming of the E4OD
transmission in my class A motorhome, with respect to shift scheduling and torque
converter clutch control, and my inability to find an existing aftermarket controller that
would do what I wanted, I ended up building my own. It took me about two years from
concept to working prototype, but I’ve got it done, and it’s working well.
It’s what I call a “ semi-automatic controller “. Park, Reverse, Neutral, and
Manual 1 operate as stock OEM. Manual 2 operates as stock OEM with the exception
that the operator has manual control over torque converter clutch application and release
In Drive, the operator has complete manual control of gear selection, and torque
converter clutch application release, subject to minimum qualifiers with respect to engine
RPM and vehicle speed. Coast clutch application and release are automatic, as is line
pressure. Line pressure is directly proportional to throttle position, with separate pressure
tables for shift events, torque converter clutch application, and engine braking. The torque
converter clutch can also be applied on decel to aid in engine braking. All parameters are
user programmable to tailor the controller to the particular application and operator’s
style.
I developed it using my ‘95 E150, 4.9L, E4OD as a test bed, and when the bugs
were worked out, installed the second unit in my ‘92, 33’class A 7.5L E4OD. The E150
has about 6 months running time so far, and the motorhome has about 3 months and 5000
miles. So far, I’m extremely pleased with the results.
The controller was designed with the RV/tow vehicle application in mind, but,
there may be some performance possibilities as well.
The thought has crossed my mind that perhaps there might be a commercial
demand for this product, and I’m not the only one on the planet that would like manual
control of an automatic transmission.
If anyone out there is interested in a business venture, or just your personal point
of view, I’d appreciate a response, or you can e-mail me at robert_hiebert@sunshine.net

Robert Hiebert

PS As a side note, I’ve also developed a controller for a commercially available exhaust
brake that I’m using on my 7.5 gasoline engine with great success, and a “trip computer”
that displays “ current “ and “tank average” fuel consumption, that should work with any
EFI engine.

RJH