Will 2009 3.5 replace my 2007 2.7?

My son blew the 2.7 in his 2007 Charger SE, and I bought a badly wrecked but running 2009 Charger SXT with a 3.5 for a donor car to get the whole drivetrain to the rear end and computer/harness. When I ask questions locally, the dealership mechanics say the sawp won't work because the 09 has integrated electronics, and to put in another 2.7 (not happening!) Different gear heads tell me different things about how easy-to-complicated it is to make this particular pairing work. What all has to happen beyond swapping drivetrain and computer/harness to make this work, in detail if you know please? How much of the electronics do we have to change to use the 09 integrated computer on the 07 body (which/all harnesses?, fuse and relay centers?, abs, dash cluster, ac controls, radio, window and mirror controls, seat controlls, any wiring under the carpet, etc)? Do we need to move any mounts, bend ac lines, change power steering reserviors, splice or lengthen any part of the wiring harness, or anything else? I am mechanically inclined, but this just ain't like the old days when I could put a smallblock v8 in just about anything and have it running in an afternoon!

 

Welcome to the forum.
I am not a mechanic so I cannot help you, but I am interested in the eventual outcome of your project.

Good luck.

 

Old days are LOOOOOOONG GONE my friend. Drop a 2.7 in and sell it/trade it in and get a 3.5 car. They should have explained it a little better. In 08 they redesigned and upgraded the CAN bus from the 05-07's; the way the computer modules talked to each other and how they process information is different. Just to further complicate things, the 2.7 uses the 42RLE transmission which is controlled by an integrated PCM. Every 3.5 I've ever seen comes with the NAG1 (WA580) trans, same as the hemis those years. Problem is the NAG1 is controlled by a separate TCM that is wired in under the dash. Any modules you swap in will need to be VIN flashed (except TCM) so you don't get a VIN mismatch error. On top of that, replacing the PCM will require replacement of the SKIM (Sentry Key Immobilizer Module) as once a SKIM has been initialized to a PCM it is locked to it forever and cannot be re-initialized to another. If you try to, the PCM will lock itself. Then you need another SKIM and to unlock the PCM (that's how the anti-theft works). Just to add insult to injury, you may lose functionality (cruise control, etc) if it works at all.

Now, just to give you a bright side, the 3.5 and 2.7 are somewhat the same engine family, so if you drop a 3.5 in, KEEP the same trans and get a harness/PCM from a SAME YEAR RANGE (has to be 05-07) car, it SHOULD (and I stress should, not definite) be a fairly straightforward swap. Problem is I've seen plenty of people post about attempting these swaps but no one has ever posted about 1) finishing it and 2) how great it was lol. Hope this helps somewhat and good luck.

 

sounds complicated as I figured and I am not an engineer.

 

cool

 

Thanks for the info Hemilonestar; that's the kind of details I was looking for, but not the answer I wanted. Lol. I'll let you guys know what becomes of this project after a little further research and better planning. I put the question on a few other mopar boards at the same time, and will let you know if I learn anything new from them.

Sorry if this seems like repeating myself, but I just gotta clearly ask; in my mind it seems possible to take EVERYTHING off the 09 (including trans, dash, pcm and all modules and harnesses, etc) and make this equipment think it is still in the 09 body? That's what I was getting at when asking about how far into the wiring I would need to swap (all the way down to the seat and door wiring, or just into the dash and the aforementioned components) to fool the computer into thinking everything is intact from the 09 VIN. Anyone out there attempted putting newer EVERYTHING (2008+) into the older body (05-07)?

 

Of course it isn't the answer you wanted, the answer you wanted was "oh sure, easy peasy, you could do it in an afternoon"....came to the wrong place for that kind of answer LMAO

Is it possible for you to swap the ENTIRE wiring system of one car and transpose it to the next one? Yes. Do you REALLY want to go through that kind of effort.....just to upgrade to a 3.5, 60hp more but still can't get out of it's own way??? Most people won't try this to get a hemi!! Just stop and think how ludicrous that is...for everything to work correctly, to make it become the newer car, you literally have to pull everything out stem to stern because not only was there a CAN bus upgrade in 2008 but wiring coding and harnesses changed. That means the TIPM up front, everything connected to it, the engine harness, dash and dash harness, door harnesses, door panels, power wiring down the length of the car to the power module in the back, all ancillary modules like SKIM, ABS, airbag, vehicle interface, cluster, etc etc ad nauseum. Then even if you do ALL that, there is no guarantee it's gonna just fire right up. Electronic vehicles can be fickle things, especially when you screw with them.

Like most people who declare they're going to do something like this and are ill prepared to do so, my advice stands: replace the engine and sell/trade it in and get the one you actually want, be it 3.5, 5.7 or even 6.1. It isn't worth the the time, effort and money you will put into this trying to create a mutant they may or may not function correctly. Also like most people who declare they're going to attempt something like this, you aren't going to listen to anyone who doesn't say anything you want to hear. So I bid you good luck, post up if you actually manage to finish it, it would be a first lol.