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-   -   4.7L H.O. Swap Question (http://www.jeepgarage.org/f51/4-7l-h-o-swap-question-15022.html)

jeepweld 11-10-2010 09:58 PM

4.7L H.O. Swap Question
 
Hi folks!

I just spent a good while doing research and checking the archives so I don't ask something that has been beaten too badly.

I have an '00 4.7 WJ with a shot engine. (spun rod bearings at 130k)

The engine is out now and I have a '02 4.7HO lined up at a salvage yard. I haven't been able to see if it is a JTEC 16 tooth or the NGC 32 tooth so I have to go and look at it before I go much further. Unless it is fairly easy to swap the tone rings, I haven't looked much into that. First I wanted to ask a couple simple questions.

Assuming this '02 4.7HO is the 16 tooth version:

Should the '02 HO's pcm swap in place of my '00 non-HO pcm with relative ease? (I read that the HO should run with its own PCM which makes sense)

Anyone think my '00 4.7 tranny might have issues with the newer HO and/or its PCM for whatever reason?

Is there anything I am missing that might steer people away from this swap compared to another 4.7 from the same year?

Any help is greatly appreciated, :)


thanks,
Brian
'00 4.7 WJ
'98 5.9 ZJ
'00 4.0 5sp XJ

Scottina06 11-10-2010 10:31 PM

Re: another 4.7ho swap question
 
your main problems with be the tone ring and the tuning. Theres a few others I dont remmeber off the top of my head...sensor items. But...a good tuner will be your friend. Check out airram.com and his SCT tuner guy or B&G performance just to modify the pcm for what you need.

cheapjeep 11-10-2010 10:48 PM

Re: another 4.7ho swap question
 
My 04 HO is JTEC. It has the separate tranny control module. You should have the 45RFE Tranny so the HO should bolt up. Check under the hood (usually leading edge of hood or rad support) to see if there is a sticker saying Mopar PCM update or something similar with a date sometime in 2001 or later. This is the flash update that turns your tranny into a true 545RFE 5 speed. If not get it flashed after the swap If you have the 2 computer setup I think the harness should work with the HO computer and TCM. Good luck bud!

jeepweld 11-10-2010 11:15 PM

Re: another 4.7ho swap question
 
I knew about the potential 2nd overdrive that my tranny could have, might be nice with the HO. I guess it depends on whether this HO is JTEC or not. There seems to be no way for the dealer to tell based on the vin number from what the guy at the parts dept said. I will have to go and look at the engine. I am planning on popping off the crank position sensor and checking the tone ring that way.

So if this thing is NGC... I should be able to swap the tone rings and get an SCT tune for my current PCM? I have an SCT for my ZJ so I am familiar with what they are.

Thanks for the help so far! :D Anyone else have anything they can think of worth mentioning for this swap?


Brian
'00 4.7 WJ
'98 5.9 ZJ
'00 4.0 5sp XJ

cheapjeep 11-10-2010 11:51 PM

Re: another 4.7ho swap question
 
Bri as far as I know all HOs are JTEC If it has the finned TCM by the coolant reservoir it's JTEC .The NGC system has the TCM built into the PCM so it wont be there. Your 00 is JTEC so imo the tone ring thing should be cool. I def would run the HO PCM and TCM though cause The HO has different timing and fuel maps plus the '02 system has the updated tranny info. As Scott mentioned above there is a sensor issue. I think what he was trying to remember is the dual knock sensors. Not sure but I think I read somewhere that's a simple unplug 1 and plug in the other deal.

Scottina06 11-10-2010 11:55 PM

Re: another 4.7ho swap question
 
yep....what he said!

jeepweld 11-11-2010 12:39 AM

Re: another 4.7ho swap question
 
Sounds like a good swap so far. I am going to go check this engine out tomorrow and see if I can get the pcm and the tcm along with it if it looks good. :)

thanks a bunch so far!

Brian

jeepweld 11-13-2010 06:59 PM

Re: another 4.7ho swap question
 
Well, I have the '03 HO engine on a stand with the full wiring harness, pcm, and tcm. When comparing the two engines and wiring the things I see are the knock sensors won't function at all unless I get whatever plugs into them that must still be in the Jeep I got the engine from. My '00 4.7 doesn't have any knock sensors and it doesn't have the connector that they plug into. There are some minor differences between some of the PCM connectors and other connectors as far as the wire locations in the 32 pin and other connectors. I am not sure if I should use the HO's wiring harness or my old on since I have the HO's pcm installed. I am trying to look over the schematics of both systems to determine if I may be running into problems. There is a small grey connector that has 8 wires that are supposed to plug into something. Four of them are from the knock sensors, two come from the pcm, one omes from a small connector right near the cam sensor up front and the other goes behind the engine somewhere. I will have two connectors that will dead end from the HO's wiring harness. Maybe I need another wire harness or something simple to make these knock sensors actually work. I can take pics of these if anyone would like.

Does the HO run just fine on premium fuel having no knock sensor input at all? I am hoping the HO's pcm doesn't give me any problems with this.

thanks,
Brian

jeepweld 11-13-2010 07:47 PM

Re: another 4.7ho swap question
 
2 Attachment(s)
Here are the two connectors that are not on an '00 4.7. These are off of the '03 HO harness. Both are partially tied directly to the knock sensors. Does anyone know what these end up pluggin into and if that is something I can yank out of a wrecked HO? In the one image the smaller grey connector on the right is the one in question. The image near the cam sensor just has that yello 4 pin hanging there. I am thinking I might be close to getting these knock sensors to function if all I need is to grab the power block or something hopefully not too hard to get at out of that salvage yard. :)

cheapjeep 11-13-2010 08:20 PM

Re: another 4.7ho swap question
 
Quote:

Originally Posted by jeepweld (Post 300867)
Here are the two connectors that are not on an '00 4.7. These are off of the '03 HO harness. Both are partially tied directly to the knock sensors. Does anyone know what these end up pluggin into and if that is something I can yank out of a wrecked HO? In the one image the smaller grey connector on the right is the one in question. The image near the cam sensor just has that yello 4 pin hanging there. I am thinking I might be close to getting these knock sensors to function if all I need is to grab the power block or something hopefully not too hard to get at out of that salvage yard. :)

Quote:

Originally Posted by jeepweld (Post 300855)
Well, I have the '03 HO engine on a stand with the full wiring harness, pcm, and tcm. When comparing the two engines and wiring the things I see are the knock sensors won't function at all unless I get whatever plugs into them that must still be in the Jeep I got the engine from. My '00 4.7 doesn't have any knock sensors and it doesn't have the connector that they plug into. There are some minor differences between some of the PCM connectors and other connectors as far as the wire locations in the 32 pin and other connectors. I am not sure if I should use the HO's wiring harness or my old on since I have the HO's pcm installed. I am trying to look over the schematics of both systems to determine if I may be running into problems. There is a small grey connector that has 8 wires that are supposed to plug into something. Four of them are from the knock sensors, two come from the pcm, one omes from a small connector right near the cam sensor up front and the other goes behind the engine somewhere. I will have two connectors that will dead end from the HO's wiring harness. Maybe I need another wire harness or something simple to make these knock sensors actually work. I can take pics of these if anyone would like.

Does the HO run just fine on premium fuel having no knock sensor input at all? I am hoping the HO's pcm doesn't give me any problems with this.

thanks,
Brian

Brian I have a trip to go on tomorrow but if you can wait till Monday morning I'll pull my airbox and take some good pictures of the wiring and then maybe we can figure out what goes where from mine.I think your gonna need the knock sensors for sure. Its kinda hard to tell about the harness without seeing both.

cheapjeep 11-13-2010 09:23 PM

Re: another 4.7ho swap question
 
1 Attachment(s)
Here's pinouts of the 3 PCM connectors The knock sensors use the C3 connector so if there are any unused connectors in that circuit that might be what we're looking for.

jeepweld 11-13-2010 10:52 PM

Re: another 4.7ho swap question
 
Nice, I just got my hands on the pin outs diagrams for my '00 and my '03. I wanted to compare the pcm to at least make sure the wiring isn't different. I will go print them out now and start comparing.

Seems the HO engine has a different wiring harness than the non-HO. I am curious as to what those two connectors I have in those two pics go to. I am guessing they tie into the power block somehow.

Thanks for the pdf of those pin outs! That got me going in the right direction again. :D


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