Originally Posted by Tricey J

Ok so having said all that, can u swap out the 2.7 for a 3.5? I have an 08 magnum as well, motor locked up. I understand what u said about the PCM and transmission, but I'm a beginner and a female and this is only my second project.

Originally Posted by Magnoom

LMAO......I will start out by saying that anything is possible with enough money and know how. If you are asking here then you definitely don't have at least one of those; Hopefully you have more of the other if your common sense doesn't take over.
So, the 4.7 was strictly a Ram and Jeep engine. It was never offered in an LX and with good reason; it would've been a heavier V8 that made less power than one of the available V6's. The standard (not counting the HO, because those are as rare as hen's teeth) 4.7 from 1999 to 2007 only made 235hp. The 3.5 V6 available in the LX platform made 250hp. I feel I should mention that upgrading from a 2.7 to a 3.5 is actually a viable swap and has been successfully done. In fact there is a 4.0 V6 of the same engine family that makes a bit more power than the 3.5 and is a bolt in when used with a few 3.5 parts. The 4.7 was upgraded for 2008-13 with more cam timing, compression, better heads and intake manifold, to the tune of 310hp in the Rams. Regardless of which one you would try to use, it was never meant to sit in an LX chassis. You'll need custom mounts most likely. The 4.7 was also never hooked to the only two transmissions offered in the LX, the 42RLE and the NAG1. The 42RLE was hooked to the 3.7 (4.7's baby bro) so you could bolt the trans to the engine, though it wouldn't last long from the higher torque of the V8. Since the the hemi was both hooked to the RFE and the NAG1, and the 4.7 was hooked to the RFE, logically a 4.7 should bolt to a NAG1. Problem is you don't have one, you have the weak 42RLE trans. This would require more custom wiring than you're already going to have because to run a NAG1 you need a TCM wired in (2.7 PCM does double duty for engine & trans). Your stock PCM is designed for a V6 in a CAN bus environment. The only CAN bus 4.7 installs were again, Jeeps and Rams but different bus speeds so you can't just integrate one of those PCM's into the car. Even worse with the 2008-13 4.7 because it has twin plug heads. The only way I could possibly see this working would be to convert the car to a hemi car PCM and TCM setup, then wire it to the engine and get a custom tune to DETUNE the stock parameters. By this point, you'd be better off swapping in a 5.7 hemi.

I have to ask, what led you to this idea? Have an 08 Magnum with a blown up 2.7 and someone offered you a 4.7 or you found one in a junkyard and though that might work?

Originally Posted by Steven Hollis

Originally Posted by Magnoom

Originally Posted by Swansonb007

I just had to say I appreciate your knowledge and love your replies! People need to relax. Especially when the ones seeking advise! Which leads me to, I am the original owner of a 2005 magnum r/t 151k miles. Still registered and on the road. My question to you is I've never changed the transmission fluid and I do have the correct dipstick to read the levels, however does no good when you don't know what ever little measurement slash should read when engine hot, cold, ect or at this point is it worth even risking trying to change or finding a proper mechanic who can without being charged what on of these engine swaps would cost..lol. Just goes into gear kinda hard and you hear low thump. I've only ever used 89 octane gas, oil change every 5k miles, stage II chip and Borla cat back exhaust. While im asking i get the airbag recall flyer and have not brought it to a dealership for the free replacement they say, but I don't trust the dealership and do you know what exactly they replace and will they just probably mess something else up if I let one of there technicians touch it? Sorry for long reply and keep the sarcasm the world needs more of it. Respect.

Originally Posted by Swansonb007

My question to you is I've never changed the transmission fluid and I do have the correct dipstick to read the levels, however does no good when you don't know what ever little measurement slash should read when engine hot, cold, ect or at this point is it worth even risking trying to change

Originally Posted by Swansonb007

I've only ever used 89 octane gas, oil change every 5k miles, stage II chip and Borla cat back exhaust.

Originally Posted by Swansonb007

While im asking i get the airbag recall flyer and have not brought it to a dealership for the free replacement they say, but I don't trust the dealership and do you know what exactly they replace and will they just probably mess something else up if I let one of there technicians touch it?

Originally Posted by Steven Hollis

from a 2.7 to 4.7 r 5.7 which is more feasible