Welcome to Allpar. It would vary by application and year. Some PCMs were Jeep/Truck only (JTEC- Jeep/Truck Engine Controller).
Cummins diesels had a Cummins ECM mounted on the block to control injection with a Chrysler PCM 'slave' unit on the firewall taking care of Torqueflite shift/lock-up and miscellaneous duties like charging system voltage regulation, A/C compressor, etc.
Some PCMs were passenger car/minivan only. The NGC (Next Generation Controller) was used in cars, trucks and minivans. It was phased in as electrical architecture and model lines changed from 2002-up. I think that the latest iteration of NGC is the NGC4 and is used in both cars and trucks.
The GPEC (Global Powertrain Engine Controller) is the latest passenger car PCM and was introduced in the 2007 World Gas Engines.
To answer your question, I think that the 2008 Ram and 300 would use the NGC series of PCM. You would want to view connector pinout diagrams to make sure there was a match for inputs and outputs.
Chrysler PCMs used through the years are described briefly here:
http://sweet-sauer.com/2013/01/27/pcm-programming-pointers/

 

There are several or more hardware PCM's in use at any one time. Even if one hardware PCM is used for several models, the software is tailored to each model/engine/transmission combination.

Chrysler has a system in place to prevent mixing up the software in the vehicles. The Part Number for the PCM identifies the software loaded in the PCM, so the same hardware PCM will have a dozen or more part numbers according to what is loaded in it. The tools that can reflash and interact with the PCM are designed to read and react to the particular part number of the PCM, so a tech can't screw up and accidentally load/reflash the wrong software or update.

So, even though its the same physical computer/hardware, for all intents and purposes, its a different computer based on model/year/engine/trans combination, because of the software loaded in it. I "think" the only way around it is hacking.

 

It is recommended not to swap computers between cars if this was your intention. Even if the connectors plug in OK.
Sometimes a foreign module does not play nice with others on the communications bus. Firstly would be a 'ck eng' light for 'mismatched VIN'. Secondly would be a SKIM key secret code mismatch where the vehicle could not be started.
Like a 'virus', other modules may have to be replaced if the wrong key code gets passed around. Other modules may try to 'learn' the identity and options of the implanted module. This can be thousands of dollars and dealer-only to rectify. If you are 'hacking', be prepared to be unsuccessful.

 

Without the replacement computer being programmed with the vin number and a few other things this will cause major problems. I would liken this to putting a computer operating system on your home computer from another computer when your computer has different hardware in it.
So you turn on your computer with the different operating system and you discover that your keyboard, sound card, video, card, and memory card reader do not work. Now you basically have a computer that is useless.

 

The subject is very broad, and computer use has grown and changed tremendously over the years, we are tossing out a lot a concepts that is confusing the situation.

If you're talking about swapping around PCM's between models, it is extraordinarily unlikely to work. It's extremely unlikely to work trying to swap within the same model of the same year, with different engines and transmissions. You need to look up the part number PCM you need and use that part number. Yes, 15 years ago, in a few cases a PCM for the same model but different displacement version of the same engine might work, NOT as well as the right PCM, but it worked.

Since the late 90's there has been evolution of multiple computers communicating on multiple buses, as well as immobilizing and anti-theft features that ka9yhd and IC were talking about. This just complicates it even more and makes it even more unlikely plugging the wrong PCM in would result in it working anyway, despite being the wrong PCM.

 

Thanks alot guys. You answered my question. Am looking at putting a 5.7 and transmission in my 85 Ram. My son is also looking at a 5.7 in his 06 Ram to replace the 3.7. Looking at all possibilities. Looks like it would be more simple to have the PCM in the 06 Reflashed for the 5.7. Would probably have to get everything to refit the 85. Motor, Transmission, Wiring harness, PCM ect.

 

Flashes only update to a newer software release for the same PCM application. A PCM will always retain it's core identity. A 3.7L PCM will always be a 3.7L PCM. It can't be 'made' into a 5.7L PCM with a flash. That core identity is locked in.
You would probably also want a fairly complete '06 5.7L donor truck to change his 3.7L truck over. You will need harness, PCM, linkages, transmission, exhaust, cooling, modules, cluster and all the miscellaneous bits and pieces that go along with it. It would be a massive undertaking.
You may have to re-register the truck as the original VIN would now be incorrect. It may violate federal emission laws. I don't know about local state emission or DMV laws about modifying vehicles to this extent.
It would be more worthwhile just buying a good, used Hemi truck instead.

 

Flashes only update to a newer software release for the same PCM application. A PCM will always retain it's core identity. A 3.7L PCM will always be a 3.7L PCM. It can't be 'made' into a 5.7L PCM with a flash. That core identity is locked in.
You would probably also want a fairly complete '06 5.7L donor truck to change his 3.7L truck over. You will need harness, PCM, linkages, transmission, exhaust, cooling, modules, cluster and all the miscellaneous bits and pieces that go along with it. It would be a massive undertaking.
You may have to re-register the truck as the original VIN would now be incorrect. It may violate federal emission laws. I don't know about local state emission or DMV laws about modifying vehicles to this extent.
It would be more worthwhile just buying a good, used Hemi truck instead.

I understand the desire to upgrade what he has, but IC is absolutely right. If his current truck has features he must have and can't find in a used Hemi truck, swapping them in would undoubtedly be easier than what he wants to do.

 

Those days of changing drivetrains for whatever purpose are long gone. It is way to expensive, complicated, and in some instances as IC says, breaking emmission laws. Plus, I wouldn't think that a 6 cyl rear end would take the abuse of a Hemi either. Brake systems wouls also need to be upgraded. Engineers got this stuff down to a science when designing new vehicles for all the safety. emission stuff, and fuel mileage requirements they have. Buy a Hemi truck.

 

In an earlier post, I spoke about the system Chrysler has in place that identifies the PCM by a part number based off the Software Loaded in it, NOT the physical computer itself, as well, the Service system is setup to check the part number and only flash software updates for that particular part number, to protect against Tech's making mistakes. As far as I know, the only way to load software for a different engine on a PCM of the wrong part number would require hacking, the time and effort would likely cost way more than just purchasing a new PCM of the correct part number.

Engine/Transmissions/Drivetrain Swaps in modern vehicles are NOT as simple as the old all mechanical systems. Wiring harnesses will be different as well as all the electronics. It will likely require swapping the entire drivetrain, all the wiring, electronics and emissions. As well, it will take some time with the dealer and them getting corporate to change the Database for the VIN# for the equipment on the vehicle, otherwise any service and use of Proprietary tools could result in all sorts of mess ups. And finally, the drivetrain electronics will have to talk to the body and safety electronics as well, at the very least for anti-theft features, that could cause all sorts of problems as well.

Its not as simple as the old days, were you just dropped an engine on hand that fit the bell housing pattern into the bay, maybe have to do a little welding to adapt the mounts and splice a couple of wires.

 

I saw somewhere a general breakdown of PCM/ECU version's by year. I can't find it now but it was a little vague. It covered 80's-2021. My main interest is LX cars but as mentioned base hhh hardware was used across all models.
I've got a 2006 Charger 3.5 that needs an engine. Unfortunately, only 2005-2006 engines are a direct bolt up option. Looking at computers, they are the same situation. The cam sensor is the main difference between 2006 & 2007. Wire colors are the same, just different plugs. Could I just swap the plugs out and be okay?

 

Welcome to Allpar. They usually change change the connector a following model year for a reason (to prevent the wrong part being installed?).
Chrysler (or Mopar) don't say that the 2005 and 2006 can interchange. It can be bad swapping major modules. It is always best to use the correct OEM module for the car.

A big change in cam and crank sprockets in the early 2000's a the switch from SBEC III to NGC.
There is a heart-breaking Youtube of a guy installing a 2002 V6 in a 2003 Liberty and getting a no-start because of this change.

I use the Mopar reman catalog to see what years, applications and part numbers will work. Since they want to keep the amount of different part numbers to a minimum, they will keep it as accomodating as possible.
As with most any interchange info, it will say what works, but won't say why another part doesn't work or what is different about it.

AFAIK, all LX are NGC IV modules.

 

Welcome to Allpar. They usually change change the connector a following model year for a reason (to prevent the wrong part being installed?).
Chrysler (or Mopar) don't say that the 2005 and 2006 can interchange. It can be bad swapping major modules. It is always best to use the correct OEM module for the car.

A big change in cam and crank sprockets in the early 2000's a the switch from SBEC III to NGC.
There is a heart-breaking Youtube of a guy installing a 2002 V6 in a 2003 Liberty and getting a no-start because of this change.

I use the Mopar reman catalog to see what years, applications and part numbers will work. Since they want to keep the amount of different part numbers to a minimum, they will keep it as accomodating as possible.
As with most any interchange info, it will say what works, but won't say why another part doesn't work or what is different about it.

AFAIK, all LX are NGC IV modules.

View attachment 81794

I don't see 2006 year shown. I've looked up engines and most references show 2006 only for the 3.5.
From what the system says, 2006 had a 5 speed auto and the 2005's had 4 speed auto so they won't work. The situation here is the oil pan. The bolt pattern for the transmission side is different. The pan bolts to the engine fine. I've done it. The transmission holes are just way off.
Apparently, Dodge didn't offer the 5 speed in 2005. Then in 2006 It was the only option. Then in 2007 You could get either one from there on out. Ran into this twice in the last few months. 5 speed cars have the Auto-stick option. 4 speeds don't is the easy way to tell I've found so far.
The other issues have been the cam sensor being different and the AC compressor not fitting either. It can be a mess swapping years on these cars. Especially 2005-2006 years for the LX bodies.
The 4.0 & 3.5 externally are the same. Doesn't matter if its FWD or RWD. They will swap either way but you have to watch the years. Intakes and exhaust are diffetent but you can just swap them out. 2007-10 your pretty much okay. It's the 2005-06 years that throw a kink in the plan. I'll find out soon whether or not you can use the different 2007+ sensor on the 2006.
On the 2002-2003 Swaps, it is a difference in the tone wheels. 2002 had 16 teeth/windows & 2003+ has 32 teeth/windows. Most engines have them bolted to the last throw on the crank. You can unbolt them and install the correct tone wheel and your all good. I've done it on a 2002 Ram 1500 4.7l. Used a 2004 Engine in it after swapping tone wheels. Some engines have them cut into the crank so your out of luck if that's the situation. Unless you swap cranks.

 

These kinds of jobs with computerized powertrains are mostly the domain of specialty shops. The 5.7 Hemi and (presumably RFE) AT swap into a pre-OBD2 truck wouldn't really be problematic, and since the engine is newer than the truck, Federal emissions are a non-issue. Maybe expensive - a stand-alone controller and harnesses could run several hundred to $1000 - just need a stand-alone controller to run the engine/trans combination, plus whatever else you need to beef up. There's a big delta between an 85 and an 06, powerwise.

 

I see tons of Hemi swaps into older cars and trucks on my hotrod shows all the time, yet as indicated on here it'd hard to do and very expensive. To this I disagree because buying a good used 5.7 with all wiring intact from a wreaker is just a cheep as buying a original replacement for said vehicle. Motor mount and tranny mounts are the hard part. Getting a computer reflashed for the set up seems simple too. The other hard part is finding someone near you that can reflash the PCM(well at least for me it is).

It would be expensive if you have someone else do all the work for you, but for us Hot-Rodders swapping a modern Hemi into an older car/truck is a dream come true.. can't wait to see how you do on your projects @Larry Bartee