Jeep Wrangler Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
1,193 Posts
Discussion Starter #1
I seen and read that some YJ owners are running Grand Cherokee alternators and that it is (basically) a direct bolt in. However, that the wiring harness needs to be changed / altered to account for the higher electrical supply.

Can someone expound on this a bit? What year / model type of Grand Cherokee works and what parts would I need for the wiring?

Also btw, wanted to run a higher amp alternator because I'm a little electrical heavy and I do want to add a winch in the near future, single battery setup. Not liking the price of those mean-green alternators lol so I was thinking I could grab one from the junkyard from a GC.

Thanks Gents,
 

·
Registered
Joined
·
1,193 Posts
Discussion Starter #3

·
Registered
Joined
·
1,193 Posts
Discussion Starter #4

·
Registered
Joined
·
4,180 Posts
You need a late 1990's denso alternator off a dodge ram or grand cherokee with connections like this



The later Denso's that look like this will not work without hacking up the plugs on the back





The factory charging wires should be upgraded. The + wire that comes off the rear post is black it will look like a ground but it is not. That wire runs into a loom and up to the power distribution center mounted in front of the battery. It runs into 2 smaller wires red wires that are fused inside the PDC. There are 2 fuses i cant remember what size the fuses are off the top of my head i think they are both 50 amp. You will not need them anymore.

Run a heavy gauge wire off the + post on the new alternator and fuse it then straight to the + post on the battery you do not need to run it to the PDC anymore. Pull the 2 50 amp fuses in the PDC so the old alternator wire will not have power to it.
 

·
Registered
Joined
·
4,180 Posts
This is how i did mine with a 120 amp alternator. I have a 2 gauge wire coming off the + alternator post runs to the fender where i have a Blue Sea fuse block with a 150 amp fuse then it runs to the + battery post. All of the Grounds are 2 gauge also. I also have a new 2 gauge + wire running to the PDC block and the starter.
 
  • Like
Reactions: 9T4YJ

·
Registered
Joined
·
4,180 Posts
I got all of my battery cables from Marine Wiring, Boat Cable and Electrical Genuinedealz.com you can get them built to order any way you want them and the prices are fair. This guy does really good work i buy all of my cables from them and they have free shipping. They are a seller on ebay and have really good reviews.

I use military battery terminals to connect them all. You just have to measure the size of the studs you need and lengths. I ordered all of my cables with heavy duty lugs on them. In hindsight it's overkill and i could have went went with standard lugs and it would have been fine.
 

·
Premium Member
Joined
·
2,705 Posts
I seen and read that some YJ owners are running Grand Cherokee alternators and that it is (basically) a direct bolt in. However, that the wiring harness needs to be changed / altered to account for the higher electrical supply.

Can someone expound on this a bit? What year / model type of Grand Cherokee works and what parts would I need for the wiring?

Also btw, wanted to run a higher amp alternator because I'm a little electrical heavy and I do want to add a winch in the near future, single battery setup. Not liking the price of those mean-green alternators lol so I was thinking I could grab one from the junkyard from a GC.

Thanks Gents,
Just from memory, the mean green alternators did not fare well in post install reviews. consensus was not worth the money.. no appreciable performance.


I've seen a few threads where people did the alternator upgrade and fried other parts of the electrical wiring due to improper wiring. I'd be very careful and do your homework. I think Agalloch went a little above the bar on his, but its bulletproof, and he seems happy with the results.
 
  • Like
Reactions: agalloch07

·
Premium Member
Joined
·
2,705 Posts
This is how i did mine with a 120 amp alternator. I have a 2 gauge wire coming off the + alternator post runs to the fender where i have a Blue Sea fuse block with a 150 amp fuse then it runs to the + battery post. All of the Grounds are 2 gauge also. I also have a new 2 gauge + wire running to the PDC block and the starter.
You should dig up your post from when you did your alternator upgrade and re edit it for what you would or wouldn't do differently. it was a good read when you were in the middle of it, now you've run it a while I'd like to know what you think could be streamlined a little for those with a tighter budget.
 

·
Registered
Joined
·
4,180 Posts
Just from memory, the mean green alternators did not fare well in post install reviews. consensus was not worth the money.. no appreciable performance.


I've seen a few threads where people did the alternator upgrade and fried other parts of the electrical wiring due to improper wiring. I'd be very careful and do your homework. I think Agalloch went a little above the bar on his, but its bulletproof, and he seems happy with the results.



I went though 4 Mean Green starters under warranty and when the warranty ran out i bought a Advance Auto replacement and it lasted a good 8 years. I would never buy another product made by Mean Green
 

·
Registered
Joined
·
4,180 Posts
You should dig up your post from when you did your alternator upgrade and re edit it for what you would or wouldn't do differently. it was a good read when you were in the middle of it, now you've run it a while I'd like to know what you think could be streamlined a little for those with a tighter budget.



I am bad at tracking down old threads, there is nothing i really regret or would have done differently anyways. Except maybe buy a larger alternator but it would have been a lot more expensive than the Denso reman i bought off rockauto.com.



Wrangler Power Products would probbaly be a good place to buy a true high output alternator but they are probably over $500. The Denso 120 amps are a nice upgrade from the dinky alternator that came on the YJ and they are the same price as a stocker.
 

·
Registered
Joined
·
4,180 Posts
I should add that if you want to run a + power post you can reuse the old charging cable for the factory alternator to power it. Just cut it off however long you want it crimp a ring terminal on it and put the 2, 50 amp fuses back in the PDC box. Then you have a 100 amp fused power wire you can put on a Blue Sea post you can use to power accessories. I am running a ViaAir compressor, Headlight Relays off mine right now.
 

·
Registered
Joined
·
690 Posts
A while back, I did the same Ram/Durango alternator upgrade that agalloch07 did. Much better performance from the charging system now. When I run the winch, the voltage meter barely notices. I made my own battery cables, because I just wanted to. I forget where i ordered my cable from though.
 
  • Like
Reactions: vmxwinn

·
Premium Member
Joined
·
2,705 Posts
For those of you with more Alternator upgrade questions, Check these guys out. They have a lot of answers.

https://www.dbelectrical.com

I replaced mine with a 78 amp from Napa which works well for me with the stock wiring setup. but then I don't run much else electrical except my winch. Once you get away from carbs and into the injected models the charging system regulates through the computer and other considerations apply.
 

·
Registered
Joined
·
4,180 Posts
I used a 120 amp DENSO 2100151 because Denso was the original manufacturer and they use quality Denso replacement parts.

The problem is that they dont offer the 136 amp with the YJ style connector on it. The only way i have found the 136 amp alternator is getting the newer 2000ish+ connector. I did not want to hack up my wiring harness so i just put the 120 amp on it. I dont have a lot of lights and other bolt on crap to power so it works for me. I haven't done any heavy winching yet but it will charge better than the dinky factory 90 amp.
 
1 - 16 of 16 Posts
Top