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Hemi Swap Complete - 2002 4.7 to 2003 5.7

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Old 03-07-2011, 12:16 PM
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Default Hemi Swap Complete - 2002 4.7 to 2003 5.7

My 4.7 kicked the bucket so I chose to put a hemi in its place. The hemi swap is complete and the truck runs pretty good. It took about 3 months or so, doing a little after work and on the weekends. The holidays made things difficult with much to do. I did this outside in the driveway in the middle of winter in western maryland (truck won't fit in the garage). We got a few feet of snow over this time as well as really cold temps and crappy winds.

I did a lot of research before I bought the hemi. I read damn near every post in this forum and others that contained the words "hemi", "swap", etc. I also got help from 2 guys in this forum. The only oversight I had was the exhaust. I doubted that my 4.7 Y pipe would work out with the hemi manifolds, but it wasn't a show stopper and deep down I wanted headers anyway. They were cheaper than an aftermarket Y pipe/cat assmembly for the 03 hemi, so that was a pretty easy decision. If I didn't go with headers, I could've had a shop fab something.

The most time was spent doing research, waiting for parts, and cleaning up/painting the engine before install. I made sure the junkyard was going to give me everything I needed. However, the junkyard sales guy had a lot less time to talk to me after I paid them. They cut things they were supposed to save, left out some parts, and took FOREVER. I spent more time dealing with these a$$holes than I did the install. Long story short, they paid me for all of the new parts I had to buy plus some, so it turned out ok. And the sales guy was fired for promising me and others too much!

Parts needed for 2002 4.7 -> 2003 5.7
2003 hemi engine w/ accessories - I realize the 03 isn't the best for tuning and has possible valve spring issues, but I was looking for ease of install. I can always go to a 2004 wiring harness later for tuning. I also plan to do the valve springs this summer when it warms up.
PCM + TCM
Both engine mounts
Both Radiator Hoses
AC Hoses - Need both hoses coming from the compressor. The alt/compressor switch sides from the 4.7 to the 5.7 so the lengths are different. I kept the same condenser and accumulator.
Heater Hoses - I bought 2 bulk pieces of heater hose to flush my heater core prior to the swap. I cut them to size to use with the hemi. I will eventually replace them with right ones that are curved appropriately so it doesn't look so ghetto.
APPS - Accelerator Pedal Position Sensor. If you didn't know, this is a little box that mounts under the battery. It has a throttle cable that is connected to the gas pedal and an electrical cable that runs to the PCM. 4.7 had a cable straight to the throttle body.
Air intake - I think the stock airboxes are different, but I'm not sure. I made a CAI from PVC anyway so I just pulled the 4.7 airbox assembly.
Fuel line - Hemi came with a good bit of the fuel line. All we had to do is get a compression fitting to attach it to the one on the truck.
Exhaust - I ended up going with Pacesetter longtube headers + Y pipe (no cats), so the exhaust is new from front to back. Trying out a 3" in/out Thrush welded stainless steel muffler. It was about $40 and think it sounds great.
No SKIM system - I made sure the PCM I was getting didn't have the ignition key security system. As I understand, a $100 and 1 week turn around will take care of this by sending it to a dude to flash it, but I was looking to save dough and time.

I put a new water pump on it just because. Also new pullies, belt, valve cover gaskets, intake manifold gaskets, oil pan & gasket, and I ditched the fan clutch because I already had an e-fan setup. Lots of wire brushing and a little hemi orange paint.

Wiring
Since the 02 4.7 and 03 5.7 both use the C130 plug into the dash, there are minimal differences. I did not have a wiring nightmare like some others, which is why I opted for the 2003. I had to run 6 wires for the APPS and change up the ambient air temperature sensor circuit. I still might have to cross a few other wires, but nothing too major. I have an Evap CEL P0443 that was there before the swap. I think it is the purge solenoid, but not totally sure. My vapor canister is busted up too, but I tried to duct tape it for the time being. Otherwise, I have P0593 Cruise and P0571 Brake Switch A circuit which I will explain below.

Problems
* Cruise Control - 02 4.7 uses a vacuum/servo for cruise. 5.7 is completely electronic. To solve this, I may or may not need new cruise control buttons on the steering wheel. (I had a 2003 clockspring so the buttons might be ok). After that, I just need to get the extra wire back to the PCM. I don't use cruise anyway, so this is not a priority.
* Brake Lights - This is a bigger issue. The tail stop lights are always on when the truck is "on" or running. Brake switch is good, it works perfectly when the truck isn't on. 3rd brake light works well all the time since it is hard wired to the switch and isn't on the same circuit as the tail stops. Maybe completing the cruise circuit will help this issue, not sure yet. I think the FCM is outputting the signal to the lights for some reason.

Otherwise, truck runs good, shifts good, and for the most part, everything works. All of my gauges, lights, and interior controls still work. Thanks to VLSGunner1 & HemiDak-Quad for helping me out. Also to berndog67 for a good thread full of info and to Weedahoe for the service manuals and part catalogs.
Sorry for the super long post. Hopefully it will help someone out.

Pics are mostly crappy phone pics. I wanted to get more pictures, but I was freezing my ace off and trying to make progress. I will upload pics of the engine installed and the actual truck soon. My CAI is still white PVC so I'll get that painted first.

Update 5/2/2011
- Figured out the brake light issue. V30 on the brake switch went to the cruise servo in the 2002 4.7. In 2003 5.7, it just needs to splice into Y135 (FUSED IGNITION SWITCH OUTPUT (RUN-START)) before the I/P -> Dash connector (C219). Brake lights work correctly now
- Cruise Control almost solved. Found cruise switches from a 2003 hemi truck. They have 3 wires instead of 2 like mine had. The 3rd wire on each switch get spliced together, then sent through the clockspring on their way back to the PCM as V38. I added the 3rd wire to the wiring harness in the steering wheel and soldered new connectors to mate it all up. It still doesn't work, but I'm going to look at the diagrams some more and see what I need to do to figure it out.
- I also decided to upgrade the evap stuff to NGC. Got a used Evap Purge Solenoid and wired it up to get rid of the P0443 code I had. I also just got the newer NVLD pump to replace my Leak Detection Pump. Pretty much the same thing, but it has one less pin. I will get it installed tomorrow. At that point I should be CEL free.

PICS
Engine came with some oxidation, but we got it cleaned up pretty good
DSCN0679.jpg?t=1299517111

DSCN0678.jpg?t=1299517111

DSCN0677.jpg?t=1299517111

Had some time while waiting for parts, so I got a little hemi orange on it. Here we just put it on the hoist and are taking it outside to drop in.
IMG_0356.jpg?t=1299517274

IMG_0357.jpg?t=1299517272

IMG_0359.jpg?t=1299517362

IMG_0362.jpg?t=1299517455

IMG_0363.jpg?t=1299517456


VHT header paint inside and out...wanted coated ones but had to cheap out
IMG_0382.jpg?t=1299517735
 

Last edited by T-Muns; 01-02-2013 at 02:33 PM.
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Old 03-07-2011, 12:26 PM
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Great work man hope you sort out your two little problems soon. the engine looks sweet painted up.
 
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Old 03-07-2011, 05:26 PM
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Originally Posted by Denniss66
Great work man hope you sort out your two little problems soon. the engine looks sweet painted up.
Thanks man!
 
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Old 03-07-2011, 05:32 PM
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looks good...im loving the beer in one of the pics
 
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Old 03-07-2011, 05:33 PM
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GREAT JOB!!! You don't know how many headaches you averted by using an '03 instead of an "04+ Hemi... err maybe you do... LOL...
 
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Old 03-07-2011, 07:18 PM
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Outstanding! Congratulations, I'm going to send this to someone I work with who has a high mileage 02 w/4.7.
 
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Old 03-07-2011, 07:34 PM
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great job brutha...by bro in law is doing a hemi swap into a dak and he's in that research mode now...
 
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Old 03-08-2011, 11:07 AM
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Excellent job and THX for the pics. Im taking my 04 PCM and harness off soon if you are interested.
 
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Old 03-08-2011, 12:05 PM
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Originally Posted by JDG103
looks good...im loving the beer in one of the pics
Thanks...Ha, yeah I forgot to mention budweiser in the parts list!

Originally Posted by HemiLonestar
Outstanding! Congratulations, I'm going to send this to someone I work with who has a high mileage 02 w/4.7.
Thanks! Cool, I was hoping someone will get something useful out of this experience

Originally Posted by HammerZ71
GREAT JOB!!! You don't know how many headaches you averted by using an '03 instead of an "04+ Hemi... err maybe you do... LOL...
Originally Posted by weedahoe
Excellent job and THX for the pics. Im taking my 04 PCM and harness off soon if you are interested.
Thanks guys! Yeah Hammer the swap was a big enough project, I didn't want to add a wiring nightmare and more time . Weed - I will eventually want that, but honestly I'm probably a year away! Just bought 4.56 gears (4x4) and getting them installed probably next week. So with the engine swap, gears, and the little cosmetic things I need do, I need to cut the truck spending for just a little while.

I'm also thinking I'd like to actually drive the truck for a little bit before another major mod.
 
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Old 03-08-2011, 01:05 PM
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Man, with a new engine and new lower gears you will have a whole different beast on your hands
 

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