2003 ECM / TCM harness for conversion

[Andres]

This might be a pipedream.



A friend of mine bought a 2003 quadcab and wants to use the driveline in a conversion. He would like to move the 5. 9 and 48RE over to a HMMWV and use the stock HMMWV gauges. He'd like to eliminate the cluster, PDC, FCM etc. Most importantly, he'd like to keep it as simple as possible and easy to troubleshoot.



Painless Wiring apparently makes a harness that just controls the 5. 9. They listed one that incorporated the 48RE, but never actually manufactured it. That would have been perfect. You can probably get a standalone TCM for the 48re. I'm fairly sure he can knock out the gauges one at a time. Additionally, his donor truck uses a Sentry key, which if unplugged, wont allow the truck to fire. I am guessing that's an ECM reprogramming issue? The dealer wanted him to bring the truck in to reflash the ECM, the RAM truck is in peices (I suggested he tell them that and take in the title).



I did part of this conversion with a 2003 Ram and '93 Hummer, but I moved the cluster, PCD and FCM over. That worked but he is more of a purist than I.





Any direction? If there is a simple wiring patch for the motor side, and he just needs a transmission controller, that's a good start.



Also, if anyone needs parts off his donor, PM me with what you want and I'll put you in touch with him.



Thanks in advance.

 

[Bob4x4]

The dealer can not change the ecm backwards to no sentry key. I have heard rumours that Bosch motorsports has a stand alone ecu.

 

[cerberusiam]

I don't know of a stand alone TCM for the 48RE. The only optiojn I am familiar with is ATS's conversion kit which replaces the VB with a proprietary one with software to manage it, about $3000 worth of parts and software.



Just how much of a purists is he??



The ECU can be reflashed to the standar dCummins tune sans all the Dodge controls which should get rid of the sentry key. Gets rid of all the trans controls and other useful stuff also.



For simplicity vs cost vs functionality the way you did is about the best compromise. That Sentry key does suck though and not sure what it would take to disable it. Might talk to one of the conversion guys and see if they have ideas.

 

[Bob4x4]

The ecm can be emptied and loaded with out sentry but not with what the dealers have

 

[Andres]

Bob, I appreciate your insight on what the dealer can and cannot do.



So will an "off the shelf", non sentry ECM bolt on and function fine in place of the Sentry minded ECM he currently has?



Cerberusiam, yeah I see thta now, about 3K (or about twice what a reman 48RE costs without the 48RE). PCS might have one, looks about the same setup, you need the controller and a new valve body.



The other option is a 4L80e with a compushift. Not as strong, but mates up to a smaller tcase - but I don't think he's going to tow with this. That, with the painless harness for the Cummins might work.



Adapter and TCM for the Cummins



http://www.transmissioncenter.org/cummins_4bt_and_6bt_adapter.htm





Here's the Painless harness, it's worth a look and serious consideration if you do a swap with a manual transmission:

Painless Performance: 2003 2004 2005 Cummins Diesel Engine Harness 5. 9L

 

[cerberusiam]

So will an "off the shelf", non sentry ECM bolt on and function fine in place of the Sentry minded ECM he currently has?

Sure as long as you get rid of all the other controllers like the cluster and FCM. Still have to have it programmed with the VIN as the Dodge based ECM is VIN locked to the other controllers and if they are not there it doesn't not like it. May refuse to run. In that case, why buy another ECU and still have to have it programmed? Unless of course he wants to retain all the pieces like you and rid himself of the Sentry.



A 4L80E is solid option with a custom TC. When I talked to Goerend about this he felt it was possible but the biggest cost was going to be a custom TC to handle the diesel engine. The gas engine TC's are totally useless.