34blazer

Im in the research phase of removing the JTEC PCM from my '97 Ram SS/T and replacing it with the '7427 ECM and $OD. My plan is to find a bricked JTEC PCM with the proper connectors and remove the guts to build an adapter harness, then mount the '7427 on the interior of the cab while retaining a factory looking appearance. I have the necessary information to convert the 7427 to work with MPFI as well as the Ram's factory service manual with everything. The Ram uses a 46RE transmission which utilizes a fairly basic electronically controlled valve body. It only has a governor pressure soleniod with a temp thermistor/pressure transducer combo, and a 3-4 gear solenoid. Also has the converter lockup solenoid. Since the 4L60E utilizes 1-2/2-3 shift solenoids, Im trying to figure out if the 7427 can be made to work with the basic trans controls of the 46RE.

First idea:

Use a resistor(?) for feedback for the first 2 gears so the ECM wont notice there is no solenoid there. Hopefully match the calibration to the shift 1-2/2-3 shift points

Second idea: somehow only utilize a 3-4 shift point of the calibration to work with the 46RE.

Im stuck here for now and could use some insight, since Ive never messed with calibrations with trans controls. Im not worried about OBDII since the truck is smog exempt.

Thanks

Six_Shooter

iTrader: (2)

What about using Megashift to control the trans? http://www.msgpio.com/manuals/mshift/4L60e.html

I'm thinking that the $OD code would need too much re-write to get to work properly with a transmission other than the 4L60E/4L80E. Tricking the PCM with resistors doesn't work, for the solenoids, it looks at more than just resistance of the solenoid coils, it looks at the current needed to open/close them.

34blazer

Yeah I looked at megashift but it still presents the same problem, but now configuring the gpio board, which I don't know how to do that and write the code?

I also thought about using a solenoid to also simulate load and provide feedback

Six_Shooter

iTrader: (2)

The problem with just using a static solenoid is that the current will always be lower than it would be if there was fluid pressure present. It may present a problem.

I just think you'll be better off using something else for the trans control, or learning to write code, either C/C++ for the Megashift/GPIO, or Assembly for the Delco controller.

34blazer

I have a service manual for the 4l60E and have spent a few hours reading from it so far. Now from what Ive gathered the solenoid seems to toggle a check ball, while other parts bear the bulk of the load. But Im not totally sure yet, I may have to ask in the trans section for more specifics. The 46RE is really basic so I may be able to get away with developing a stategy to get it to operate properly. If something isnt working right and if I need to drive the truck, the first 3 speeds are hydraulic anyway and I can manually toggle OD. Id really like to pull off this swap but if it needs to be abandoned I can deal with it. My OCD is preventing me from giving up on it just yet.


With time Ill learn assembly and C language variants, right now I can learn mechanical/electrical faster than programming. If there was a step by step tutorial out there id be more than happy to dive into programming but everything is scattered, or was, when I stopped studying.

34blazer

bump.