Wanted to post my information for those lost souls among us (me three hours ago) who are trying to sort out what goes where and what to buy! Technically this is a 4-wire setup, but I think people are referring to it as a 3-wire. Whatever, it works. I did this swap on my 1989 22RE.

I bought the Trail Gear bracket like everyone else. It can be found on their website.



I initially ran a GM 1-Wire (NAPA P/N: 67294) for two or three years until it died the other day.




After much reading, it appears that the consensus these days is the 3-wire is better. Decide for yourself, there is plenty of information out there (see links at the end of the post). In any case, I bought a 105A Ultima Alternator from Oreilly's (Oreilly P/N: 01-0381) for $78 since NAPA didn't have anything locally. You can also reference this part via 1988 Buick Lesabre with a V8.



You will also need to buy the GM connector for the idiot light, 12V sensor, and ignition wires (NAPA P/N: EC101).



The Ultima Alternator has 5 connections, 4 of which you actually use.

-DC Output to battery, this is the post on the back
-12V Sense
-Ignition
-Lamp
-Stator, or "P"



As far as I know, we don't care about P and the connector you buy doesn't even have a wire for the P contact.

To connect your stock wiring harness to the new setup, disconnect it at the plug (driver's inner fender area) and unwrap all of that old electrical tape. You will have five wires, potentially six. I had the following:

White
White
White
Red
Yellow
Black

One of my whites was grounded to the fender wall. I don't know why, the PO must have done that because it wasn't right. I threw that out because it was not part of the five wires associated with the plug itself. The other two whites need to be connected together per the FSM -- they are intended to be connected to 12V if you read the charging chapter text and diagram at the end of the FSM. Red is your ignition, yellow is your idiot light, and I haven't done anything with black yet because it's not in the FSM -- at least not that I can see. I'm assuming it's a ground, can anyone confirm?

To review:
White/White : 12V Sense AND 12V alternator output post. Connect it all together (you may need an extra piece of wire depending on how you do it)
Yellow : Lamp
Red : Ignition
Black : Unknown/Not needed?

The following links are good references if you run into issues:
http://www.toyotaoffroad.com/Article.../chevy_alt.htm
https://www.yotatech.com/forums/f2/s...rience-268623/ (keep in mind this post is for a taco so hookup is slightly different)
https://www.yotatech.com/forums/f131...r-swap-236748/
http://www.pirate4x4.com/tech/billavista/Wiring/Part2 (if you get REALLY bored)
http://www.pirate4x4.com/forum/toyot...r-upgrade.html

I hope this helps people save time and hours researching the correct setup. If anyone has more information on the black wire from the stock alternator harness, I'd be interested to hear what to do with it. As far as I know, there is no ground wire for the alternator....right?


R5

 

Nice post, couldn't remember the applications for single pulley C130.

 

Great post ... how many amps is that GM putting out ?

 

I haven't measured it yet but it's advertised at 105A. I did a full day of wheeling out in Ocotillo and it ran like a champ the whole time. Headlights are as bright as ever.