Dead XJ Alternator..Upgrade ideas?

[WagoneerXJ]

comin back from Calgary to B.C. last night, took highway 2 to Ft. Macleod (NOT a good idea. WHITE OUTS!)...and my alternator decides to quit about 55 km's from home. Thank god my yellow optima has a long reserve.

Anyways, I figure now is the time to upgrade. I thought I heard somewhere that an alternator from a late 90's V8 Dakota was a bolt in upgrade (Higher amp output) Can anyone confirm this, or give me another option? Thanks

[Pookapotamus]

i would also like to know about this, although i have been considering going to a sealed type alt, but i dont have any information on them either.

[RckyMtnTJ]

When I got mine rebuilt, they said something about using a smaller pulley to give it more juice.  That might be an option.

[WagoneerXJ]

Well I think it will work just fine. I work at a parts store and it's a slow sunday. So I've had lots of time to sit here and cross reference this.

 The stock output 90 amp Alternator is the SAME in the XJ 4.0, ZJ 5.2 and 5.9, Dakota 5.2 and 5.9, Durango 5.2 and 5.9 and the Ram 1500 5.2 and 5.9 (probly the 5.9 in the 2500 as well) The 90 Amp has the bosch part # AL6509N (or AL6509X for a rebuilt) Now the Heavy Duty option for the XJ 4.0 is listed as an AL6510N(X) Says it's a 120 amp alternator.

 The 136 amp alternator I was told of is Bosch part # AL6526N(X) and it was a factory option on every one of those vehicles I listed, except the XJ 4.0. Those ones had the 90 AMP (Same as the XJ) or the big 136 amp. What this means to me is that the 136 amp'er will fit on the XJ just fine, it obviously uses the same mounts and wiring as the Dakota,Durango,ZJ and Ram.

 I was able to get an OEM number for the 136 amp'er so when I'm at the junkyard I can tell which one I'm lookin at. It's Chrysler # 56027913

:edit: The year range for the Dakota,Durango and Ram for these things is 97-2000. Maybe other years, I just haven't checked. For the ZJ it was up to 98, checked as far back as 95 as well with the same results

[WagoneerXJ]

When I got mine rebuilt, they said something about using a smaller pulley to give it more juice.  That might be an option.

no thanks. Don't want to under/overdrive my alternator.

[Immortal]

A little while ago, shortly before an unfortunate "badger incident" my alternator crapped out on me. I have an "unusual" configuration with my alternator, so I spent some time tracking the correct one down. After I finally found one, I took it up to the boys at ATI (in Calgary). Dave load tested the new alternator. Rating on the alt was 95 amps (stock), he got 125 amps out of it... no mods done. I was happy with the load test, and Dave said that it was pretty standard. I asked him about any upgrades that he would recommend. His comment was "for what you guys do to these alternators the stock (95 amp rated) ones are great." He was well aware of the winching, and aux lighting that I had put the old alternator through. I asked him about sealing the brushes, he said that all the "sealant" is an extra little bit of grease around the brush housings. I even asked him about "re-clocking" the end cap to assist with mud/water drainage. He took the alternator, looked at it, and pointed out to me that there were drain slots ALL around the end cap.... so "re-clocking" the alternator was unnecessary.
My opinion.... run the stock one.
Maybe Rich will chime in to confirm/correct what I have just written.

T

[WagoneerXJ]

Hmm, interesting, I will keep that in mind. I'll just be buying a used Alternator so I wanna give this a try. If not a stock one will go back into it and I won't have wasted alot of money.

[hps4evr]

i researched this issue a few years ago when the alt in my yj crapped out. i knew i wanted some more output but wasnt ready to step up to a high dollar aftermarket unit. i checked around and found a link on bc4x4.com that had the outputs from a few different common jeeps. i went with the 136amp unit from a zj. i ordered it from auto value and it bolted right in. before that though i tried the big unti from a dodge v10, it wouldnt fit. looked the same just was physically too big. the 136amp zj unit has worked fine for lighting, winching and every day use. no problems came up with it at all. and it probably cost the same as getting a stock replacment from the parts store. so that with my yellow top has done me well.

[SwampSinger]

ATI... Amperage Tech can make your alternator crank 200 amp... witha few mods of course 

Great guys there... do quality work at a fair price.  

http://www.amperagetech.com/

[WagoneerXJ]

http://www.naxja.org/forum/showthread.php?t=995555&highlight=dakota+alternator

found some more info on it. Not quite a direct swap, but close

[cLAY]

Which XJ are you working on?  The pre '92 Renix Jeeps used a different alt than the later ones. I think the later ones used the same as ZJs and Rams.

On my old '89 XJ  I had ATI bring my stock one up to 160amp, wasn't cheap. I also re-indexed the case so it would drain better but most importantly to get the brush holder at the top of the case. In the stock configuration it sits at the bottom of the case and all the mud/silt/crap accumulates there and causes the brushes to jam in the holders causing it not to charge. After I re-indexed the case my alt problems went away.

On my ZJ(with the 5.2L V8), when I installed the electric fan I fried my alt(90AMP). So I replaced it with another 90amp, and fried it again. Then I ordered an alt from a '98 ZJ with the 5.9L. The 5.9L edition ZJ comes from the factory with an electric fan and a 136amp alt. It was a direct bolt in to my ZJ but the pulley is smaller so I needed to get a new(shorter) belt for a 5.9L ZJ. I like having a smaller pulley on the alt as it spins faster and a lower RPM which means more amps at idle. Good for when the jeep is idling in summer with the AC on or in winter with the heater going or winching with the engine at idle.

Best thing is that its a readily available part, I ordered mine from NAPA and got it with the 5year warranty.

BTW my sister has a 2001 Dodge ram with the 5.9L. I compared the alt in it to my ZJs alt and they looked quite different.

[WagoneerXJ]

This is for my 98 XJ. I might just go with another stock one.  See what I can find at the junkyard tomorrow.