alternator replacement

Any ideas for a good replacement alternator?

I am looking at both new and rebuilt, some of the new ones have a better warranty.

Delco Remy, Bosch, Napa and one I haven't heard of before ..


Ultima - Alternator

Year, engine, trans, accessories. etc will help.

Johnnie Walker said:

Year, engine, trans, accessories. etc will help.

Click to expand...

98 xj, 4.0, aw4, np231

dual batteries

Currently no high amp accessories such as a winch, a few small inverters and possibly a 2000 / 4000 watt inverter, non permanent type connection.

If your alternator is failing, it could just need brushes. An alternator shop or online store are a good source. There is a relatively recent thread about this. I bought a Auto Zone alternator about a year ago. I needed one in a hurry and they are open late. Didn't have time for the brushes to come in. It has been fine and has a limited lifetime warranty. I think you can buy one from the dealer for about $170.

My alternator just bit it in my 94 xj, stock rig. Put in a Bosch 90 amp from carquest. True lifetime warrenty. Also free roadside assistance for two years.

Upgrade to a Durango alt higher amperage and easy to mod to fit, stock 136 amp. can be found at 160 amp rebuilt. Very slight grinding needed on mount and head very small with a grinder.

Years ago I purchased a rebuilt alternator online from a re builder who said it could be rewound to 170 or 200 amps. Turned out that the casing is the same as the Grand Cherokee ... Grinding on the engine block and bracket would be required for installation. I am not sure of the quality ... More expensive HO alternators usually use better quality parts, sometimes engineered differently than your stock alternators.

My main concern is the current reman. Delco Remy alternator, three years old, the field terminal voltages are too low. Same results were produced using another PCM. I haven't yet tested the wiring for the field terminals ...

Possibly it could be the ~6 year old battery, but suspect the problem is with the alternator. Charging voltages fluctuate from ~12.5 to ~13.5, (previously produced a steady 14+ volts.)

Noticed the problem after a P1682 mil appeared.

Which ever you choose, be sure to measure the pulley diameter BEFORE you install the replacement. It may come with a different sized pulley, and your belt won't fit.

You can just swap in the stock pulley if need be....

I'm not sure if the problem is the alt. or wiring, etc. The pcm tests ok , field terminals read approx. 13 volts / 5 volts ... max. alt. output is 13.5 volts.

Continuity of wiring checks out, no known opens or shorts.

manual shows one field terminal should be 3 - 4 volts less than the high 12.5 - 13.5 volt side. apparently one side is too low.