Question for Paul Herioux

[bvanetten]

I'm currently controlling OD and lockup via toggle switches. I don't have the dodge computer (or any other computer) installed on the motor or the burb and I need to know the theory of operation for the 47RH transmission to help design a controller. Fluid temp, line pressure, rpm, mph, kickdown cable? Are these the systems that the dodge controller logic uses for L/U and OD? I'm really more concerned with what values are used to determine when OD and L/U are turned off. I've already forgot to turn off the TC while stopping (bad noises and vibrations come from the transmission area!) and if you leave OD on it shifts from 2nd to third and then to fourth immediately. Have you delt with this on your transmission yet?

Bruce

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1972 Chevy Suburban with 1990 D350 4x4 CTD Chassis, 618a transmission, 12cm housing, tweaked pump, 3 1/2" straight pipe, autometer gauges

 

[Paul Herioux]

Yeah, I've experience all the bad things above except when I leave me OD switch on at a stop it stays in 4th and the truck will barely move itself. Also my trans won't do a 4-3 downshift while locked up, stays in 4th with solenoid off. Maybe Bill K. can shed some light on this phenominon(spelling??, we need a spell checker function). As for controll inputs, the factory looks at RPM, vehicle speed, TPS, engine temp, brake switch and on some models trans temp. The first three items are the most important. I am considering monitoring boost pressure when I build my controller to very shift schedule based on engine load. I have put my controller developement on hold until I can afford a TC and VB from Bill K. as I believe the shift schedules will have to be completely redown at that point. Will also have my new gears by that point as the 3. 07's are too high for the way I use the truck.
Factory specs for OD and Lock up:
WARNING:These are from memory as I no longer work for a dealer and I am no longer welcome within the doors of my former employer so I can't go look them up. I would appreciate any help you Other DC techs that are members could provide(non-member techs welcome also-just email me)
OD turns on above ~38mph off below ~32mph
below 3. 0V TPS above 3. 2V TPS
above 60*F ECT below 60*F ECT
Trans above 210*F
Lock up on above ~45mph off below ~38mph
below 2. 7V TPS above 3. 0V TPS
above 100*F ECT below 100*F ECT
I hope this info helps, if you need more feel free to contact me. I'm going to be in Dallas for a wedding this weekend and don't know if I will have net access as my laptop is broke. If you don't hear back from me till Wednesday you will know why.
I think I've ranted and rambled enough for now
Later.
brake off brake on

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The smiling ex-dealer technician
89 w250, 47rh trans, cleaned up exhaust, Dynomax bullet muffer, 3" lift, unknown oversized injectors