In over my head.... HELP!
 

Back a few months ago I decided to thrust myself I to the strange new world (to me anyway) of LS swapping my '72 GMC Sprint (el Camino) but now I realize I'm not sure what to do....
Here's my issue:

I bought a 5.3 with wiring harness and ECU out of a wrecked '08 Silverado 4x4 z71, I would really like to rewire/Repin the wiring harness myself, but cannot find a schematic for the newer E38 ECU, only for the older computers. I also was told that my '99 4l60e I have for this project will not work because its a '99 2wd tranny and I have a '08 wiring harness for a 4x4 tranny. Question #1: is there ANY wiring how-to's out there on the new harness? Question #2: will my tranny work somehow and if so, what do i need to do?

Any suggestions/help is really appreciated because I'm really starting to reconsider this whole mess!

Thanks, Richard

Re: In over my head.... HELP!
 

I am not at work so I can't help you with the wiring diagram but I think your source is right about the transmission. An '08 computer will be looking for an input speed sensor that the '99 transmission does not have.

Re: In over my head.... HELP!
 

Aww, man! Do I have to find another tranny?

Re: In over my head.... HELP!
 

http://lt1swap.com/geniv_harness.htm

I'd try ls1tech.com for questions, but make sure to search that forum for answers first because your questions are probably already answered there. For instance https://ls1tech.com/forums/automatic...rly-4l60e.html

Re: In over my head.... HELP!
 

I'd think your worst case would be to run the ECM as though it were a manual trans and then control the 4L60E with a standalone box. Neither would know about the other, but both should work independently.

Re: In over my head.... HELP!
 

Hit up clinebarger here on the forum, he is the trans guru here and does LS swaps for a living too.

Re: In over my head.... HELP!
 

E38 ECU pinouts
http://lt1swap.com/E38%20ECM%20Connector%20Pinouts.htm

Re: In over my head.... HELP!
 

What 99 vehicle did the trans come from?
I have a 4.8 out of an 08 with 4L60 trans.
I do believe the e38 ECU can be re programmed for the 4L. It is the 24 crank trigger it does not support. (If I am not mistaken).

As for the pin outs....above are what I used a few times. It has worked for me. Brenden is a beast and can also help if you have questions.

Attached is a picture if the connector on my 4L60 it is a 4x4 trans but should not be any different other than the VSS sensor is on my transfer case instead of the transmission tail housing.

Re: In over my head.... HELP!
 

Unfortunately, bigdav160 is right. You'll need a different trans because of the input sensor that is needed for the e38/t42 combo.

It is possible to retrofit at least some of the 4l60 transmissions with an ISS by swapping input shafts, pump housings, internal wiring harness, and the ISS sensor its self, but I don't know if that can be done with a '99 model or not. As suggested, clinebarger would be able to answer that question, but I don't think I'd choose that route due to the expense and/or time required.

Re: In over my head.... HELP!
 

Well, alright..... I had hoped I hadn't messed up getting this tranny, its out of a '99 tahoe, but at least I only paid $150 for it.
As far as the pinouts, this may seem stupid, but how do you know which wire is #1,#2,#3...etc? It isn't making sense to me lol

Re: In over my head.... HELP!
 

Look at the top of the page where the little picture of the connector is. Each connector is labeled (J1, X1, X2 etc). And it should show you where pin #1 is, and gives the pin # for the starting and ending pin on each row in relation to the connector. (NOTE the location/orientation of the connector itself)

So pin #1 is the pin on the TOP row all the way to the RIGHT. Opposite the large primary pin (#73)
http://lt1swap.com/E38%20ECM%20Conne...s/image002.gif

Re: In over my head.... HELP!
 

Dont panic mater! swapping trans won't be a problem. And these guys are right about lt1swap.com. that website has all the info you'll need and the guy who runs it will walk you through any problems

Re: In over my head.... HELP!
 

Ohhhh!!! It was right in front of me!! Thanks 😃

Re: In over my head.... HELP!
 

Alright, I have yet another question, what fuse block have you guys used? I keep reading about ford Taurus fuse blocks, etc... But have no clue where to start.

Sorry for all the questions guys, I just wanna get this right so I can do it again one day easier on another project rattling around my brain....

Re: In over my head.... HELP!
 

just buy one. Don't try to pull a block from the salvage yard, unless you really feel the need to use a donor block from the same truck (i.e. using an 08 silverado block to keep everything "matched").

There's a recent thread in this section talking about some of the recent problems with the fuseblocks the harness makers are using, most of which look like the cheaper wholesale blocks you can find all over.

A good quality universal fuse block is all you really need, and can be scaled up or down depending on your needs. I have 2 fuseblocks, one for my body and one for the engine/drivetrain, about 12 fuses each. Some guys slim down and put it all on one, others scale up and add extra slots or splitting things off.