ralphr87

Hey everyone!!! New to this forum and I had a few questions. Not sure if this in the correct section, if not please point me to the right section. Thanks!!!

I own a 2004 Durango that has a 5.7L hemi. Darn thing dropped a valve(which I heard is common for that year) and was looking for a motor. A buddy of mine thats a mechanic came across a guy out in Fresno area that was selling a complete engine and trans that was out of a 07 Charger R/T. My buddy did a little research for me and said that the long block from that 07 Charger would work, so with that being said and myself trusting my friend, I drove up to Fresno with my buddy and picked up the motor to use for my Durango. Well, my buddy was to busy to help me swap the motor and I really didnt have time due to long work days, so I had a friend of my dads work on it. I told my dad's friend that I had a motor and I needed him to pull my old motor, tear the new motor down, as well as my old motor, reassemble the stuff from my old motor on the new longblock and drop back in, mind you thats what my buddy(mechanic for over 10 yrs) said needed to be done. I drop off the new motor, well actually used but you get what I mean, I drop the Charger motor off and my dads friend is saying that the motor isnt going to work because the intake manifolds are different sizes and the coil packs a different and some other stuff. I explained to my dads friend that he needs to put everything from my motor onto the newer motor and drop back in my car, basically do a complete swap over. He is still insisting that its not going to work. Ive called around and for some reason no one can give me answers. This is where all you great people come in. Does anyone know if this hemi long block from the charger will work? I'm in dire need of help and opinions and my Durango has been down for about 6 months and I would really love to get that thing going again. PLEASE HELP!!!!!!!

78D200

I don't know a whole lot about the Hemi motors but if both blocks and heads are 5.7L from both vehicles, I don't see why you wouldn't be able to swap over the accessories, intake, sensors, etc. There are others on here that can answer it much better than I though.

78doubleR

ookayy..... everything should be interchangable. that guys a dumby!
The long blocks are all the same. the difference is in the intakes. you have a truck motor so the intake is set up to produce more torque than a car intake. Now they may have changed some designs in between 04 and 07 but they should all bolt up the same.

CJD AUTOMOTIVE

The '07 engine is an MDS motor. You will have to remove the MDS solenoids and replace the four lifters. You will need the block off plugs from your '04. The front timing covers, water pumps, and intakes are different for cars and trucks (that's why your guy thinks it wont work). You'll need to swap it and the oil pan. I don't remember if your '04 is an NGC or JTEC controller. That's about when they changed. Does your trucks PCM have 3 or 4 connectors?

ralphr87

I just found out today from someone that the motor I have is an MDS motor like you said. I'm not quite sure if my PCM has 3 or 4 connectors but I'll find out. Now when you say replace the lifters, what lifters are we supposed to use? Do we drop in lifters for an 04 in place of the existing lifters? And block off plugs, do you mean the block off plate for the EGR? Sorry for all the questions, not to familiar with these motors.

CJD AUTOMOTIVE

The MDS system uses a two piece lifter with oil pressure between them to regulate the valve opening. These are on 4 cylinders. (1, 4, 6, 7) You need to remove these lifters and replace them with NEW '04 lifters. You will need to block off the oil feeds that supplied the solenoids. You will see 4 plug looking things when you pull the intake on your '04 in the top of the block (it doesn't have an open valley). You will see the solenoids that need to be removed on your '07 by doing the same. Just install the plugs in their place.
The lifters are sold in sets of 4. You can tell a MDS lifter3 by looking at the side and you'll see a disconnecting pin.

ralphr87

Ok I understand now. I'll get in touch with the mechanic and give him this info and I'll keep you updated. Thanks a lot, I appreciate it!!!

CJD AUTOMOTIVE

This should be common knowledge to a competent shop/tech. If your guy is this lost before starting, your probably headed for trouble. I'd suggest finding a shop better informed on replacing the engine.

ralphr87

You have a very good point... I think I might just look for another mechanic.

ralphr87

I had one more question, will I need to do anything to the ECU or will the ECU be good?