2003 Dodge RAM 5.7l Petrol V8 ECU/ECM tuning

[DodgeRAMNZ]

Hi, I'm in NZ with limited Dodge support down here unfortunately. We've made some mods to my motor, nothing major, K&N cold air box, long tube headers etc. It runs super rich and not right. I've been trying to find an aftermarket tuning company that can provide a replacement tune suited to towing and taking into consideration the minor motor mods. Everywhere I turn suggests the 2003 Motorola ECU cannot be written to or modified and I'm stuck with a dog. Has anyone solved this problem without going to a full ECU replacement like Holley at big expense and opening a can of worms with CAN bus compatibility problems?

- Can the 2003 motorola ECU/ECM be unlocked and written to successfully?
- Can a later model ECU be swapped out that can be written to?
- Has anyone solved this problem in the past and are their companies in the US that specialize in this or similar situations?

Any advice gratefully received ...

 

[jws123]

Have not seen anyone on here tune sinetgubg that old dont think you can others will chime in.

 

[HemiLonestar]

1. It isn't locked. It simply isn't capable of what you are wanting to do. I had a mildly modified 2003. Diablo CMR can do some custom tuning with it for a mild cam but it is still VERY limited.
2. Yes. I had actually gathered the parts for this, but then ultimately decided not to go through with it. 2005 PCM and harness adapted to the truck. This gets rid of your TCM and also seriously opens up tunability. Requires adding two more O2 sensors tot he exhaust as 05's had two cats instead of the one. The 05 harness can be used but it has to be adapted to the 2003's APPS (03-early 04's didn't use the electronic pedal).
3. See #2. hotwireauto.com does this for a living. In fact they've gotten to the point where they can make that particular harness integrated with the Sound German harness to swap in a ZF 8 speed.

The 05 PCM swap and then further to an 8 sp (I HATE the RFE, was on my 6th one when I gave up) was where I was headed but after 200k miles, about 20 years and mounting electrical problems I opted to just strip the mods off and buy a newer, more reliable truck.