ive read several posts on the alternator upgrade,but still not sure which one mounts straight up without grinding or altering my brackets. I want a straight up swap.my xj is a 96 with a 90 amp alt. what higher amp alt bolts right in without modifying? thanks.

You can't go much bigger as the wiring is anemic for even that alternator. You can get a bolt on 200+ amp alternator from mechman, but you will still need to upgrade the wiring. Some parts stores have a 120 amp alternator that is bolt in but still you need to upgrade the wiring.

Now that I think about it probably would help to redo the entire harness.

explain what wires to upgrade please.and could you tell me what year jeeps 120 amp alt. parts stores carry. thanks

I have a mean green in both my yj and xj, the best in the industry..

In you winch it is a huge plus http://www.mean-green.com

I don't winch or anything. I just have a amped up stereo and some aftermarket driving lights. im looking for a parts store replacement direct bolt in. or a salvage yard find direct bolt in.

Battery mains. Member 5-90 makes some heavy replacements for the cables for the battery, starter, alternator, PDC and grounds. There's also a fusible link to the PDC that will melt if you give it too much current (it's supposed to do that to protect the rest of the system) that can be replaced with an ANL fuse. Here's an explanation:

http://www.kelleyswip.com/electric.html

Also, you can actually take your stock alternator to an alternator shop and have them upwind it for additional output. Call around your area to see if you can find an old-school alternator shop that will do that. You don't get any more "bolt-in" than that, since it's the same alternator going right back on.

i used a 136 amp alt out of a 97 zj v8 in my 96, requires some grinding and better battery cables like extrashaky mentioned

Problem solved...

Amazon 160 Amp $120 shipped...

The reviews on that seem sketchy. It seems people report having to grind down their brackets and others report there wasn't any change in juice from their 90 amp stock one. I'm replacing my alternator tomorrow, and I'll be going with the ZJ 136amp and spending 20 minutes with the angle grinder to make it fit. If I had the funds I would spring for that mean green job, but those are a bit out of my price range and really my needs at this point.

I would say stick with what you know works. If you can't or don't want to do what is necessary to make the ZJ alternator fit, then either pony up the dough for the bolt in mean green, or throw a stock replacement in.

Are you having power drain from your stereo and lights? While at idle or driving? Get LEDs.....and a better battery...or don't run your offroad lights and stereo at full power..

What battery are you running? What kind of aux lights?

all good advice ,thanks.im going to try and upgrade my wiring first.seems from my research this is big improvement over stock . jeeps already 20 years old.i need to go back and read post from extrashakey advice for wiring kit. do you recommend the 4 gauge set? what gauge is factory?1 gauge seems way overkill.

i used the 4awg, no problems. i believe it good up to 150 amps IIRC

i also used a 150 amp resetable breaker instead of the ANL fuse