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caposto 04-17-2013 07:37 PM

90A Alternator Replace or Upgrade?
I've got a '91 4.0L and looking to replace my alternator. With a Jeep it seems every replacement need is an opportunity to upgrade! I've got dual batteries now and don't really need the extra amps at the moment, but want to be ready if/when I get a winch and maybe add some more lights, etc.

I knew about the Mean Green 200A (MG1334) and also saw some others on eBay that are re-wound or something for higher amps. Searching more I see there are some bolt-in alternatives, but the information is not really complete. I was hoping to get some more info and experiences on the various upgrade options and maybe compile it in this thread.

The basics I really need to know is:

1. What is the amperage of the upgrade option (i.e. I saw a 120A, 136A, 150A, a 80/140A whatever that means, etc)

2. What is the Model and Year of the vehicle its from and/or the part number (I saw a 120A Cherokee suggested but it didn't specify the year(s) or whether it was a Grand Cherokee or not and also saw a Dakota option, again no year(s))

3. Is it a true plug-and-play option or are there modifications to the wiring, mounting, pulley, fuses, etc needed? (I saw where the 136A needed a larger gauge wire directly to the battery as well as larger ground wires from the engine and starter; Also saw something that said the 120A didn't need any wiring mods. Interesting that the 200A Mean Green doesn't mention any wiring mods necessary although I'd like to call them on that.) I imagine there are a lot of opinions on this piece so let us know your experiences.

4. Anybody have any issues with their upgrade setup.

For me I think an extra 30A from a 120A alternator would do me just fine. Especially if I don't have to re-wire.


gunslinger24 04-17-2013 08:59 PM

I've got a 94 yj. I replaced mine with a 94 Dakota alt. I think it's 120 or 130 amp. No rewiring. It was cheap!!! Think it was $100

caposto 04-22-2013 06:54 PM


Originally Posted by gunslinger24 (Post 3650000)
I've got a 94 yj. I replaced mine with a 94 Dakota alt. I think it's 120 or 130 amp. No rewiring. It was cheap!!! Think it was $100

You don't by any chance remember the brand/part number? Did you have to swap the pulley or was it the same? Thanks!

caposto 05-02-2013 02:33 PM

Any other thoughts?

goatman 05-07-2013 04:14 PM

When upgrading the alternator, it is always a good idea to upgrade the cable that goes to the battery or harness for the power. Too small a cable could be overloaded if you were to ever use all that available power. The voltage regulator connections should be the same though.

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