I am trying to source a replacement ECU/ECM. Its my understanding that the 05 and 06 are not interchangeable. I have an 06 and have part number P56044 776AD. I have found a few that claim to be from an 06 with different part numbers. Do I need to find an ECU with the exact same part number?

You did not say, what is the problem with your module?

The latest PN is:
MODULE. ENGINE CONTROLLER.
This Fits Your 2006 Jeep Liberty EDTION Limited 4x4, 2.8L 4 Cyl Turbo Diesel, 5-Spd Automatic 5-45RFE
Part Number: 56044776BB (56044776AB; 56044776AC; 56044776AF; 56044776BA; 56044776AA; 56044776AD; RL044776BB)
Any of the above PN's will work.

Another option, find one from a boneyard vehicle and get GDE to program it for your vehicle. I would call them and seek their advice. They are very experienced in this field.
Green Diesel Engineering:> http://www.greendieselengineering.com/
Office phone: (248) 977-9531

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

The positive side of the battery cable arched on the ecu causing damage

My plan was to get ahold of Green diesel engineering once I got my hands on a new ECU. They aren’t far away if I need to drive there

Have you checked with them to see if they have a spare? Also, a good used one can be programed to your vehicle. Does not have to be a new one.

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

I got ahold of them. They don’t have a spare but since I did get the eco tune from them they will help me with programming and putting the tune back on once I fine a used one.

There are a few different revs and part numbers from the 06s.

Just go on car-part.com and find the cheapest one shipped to you that you can, ask them to confirm the PN on the ecu or send you a photo. Quite a few gasser ECU that accidentally get listed as a diesel ecu.

_________________
http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Am I correct that 06 has a part number with 56044776 and 05 has a part number of 56044775?

If you are going to work with GDE on programming then seems to me the operative approach is the ask GDE what ECU PNs can be programmed to work on your 06 and quite worrying about DCJ PNs crossed to model years when DCJ PNs are often wrong.

_________________
Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs

Correct,
from my previous post:
Part Number: 56044776BB (56044776AB; 56044776AC; 56044776AF; 56044776BA; 56044776AA; 56044776AD; RL044776BB)
Any of the above PN's are for an 06 according to ChryslerParts.com.
56044776BB is the latest PN

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

Thanks for the help. Sourced an ECU.