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Alternator Replacements

I have a 2000 Nissan Maxima GXE four-door sedan, which I purchased new. In May 2008, at 39,556 miles I had to replace the alternator. In January 2011, at 45,201 miles (+5,645 miles) I had to replace the alternator again. Now, in December 2013 at 49,630 miles (+4,429 miles) I have to replace the alternator for the third time. It just doesn’t make since that the less I drive, the more often I have to replace the alternator. The replacement alternators were remanufactured and not purchased from a Nissan dealer. Do you know what would be causing the alternators to fail? Do you think purchasing a new alternator from Nissan dealer would solve the problem?

are you sure its the alternator and not something else or that you don’t have another problem that is damaging the alternators, i.e. a high powered amp in the trunk?

No additional equipment has been added to the car and it does not have a high powered amp, etc.


What condition is your battery in? How old?

Perhaps the alternator is getting overworked trying to keep a marginal battery fully charged?

As for the alternators failing, I’ve seen store-brand alternators fail just like yours. Sometimes the rebuild process is so lousy, that they just don’t last long.

Once you diagnose the cause of your problem, I highly suggest you get genuine Nissan or at least Denso alternators. They are more expensive, but were undoubtedly rebuilt to a higher standard.

Another thing to consider . . . check for a parasitic draw. Perhaps you have a draw that is moderately draining the battery every evening. And then once the car is started, the alternator is working overtime to get that battery up to full capacity.

While its true that the quality of after market rebuilds can often be questionable, it is time to have the whole power system evaluated. As keith implies you can overwork an alternator. And that can be done even if you don’t have any high-powered extras installed. E.g. a failing battery and some old cables will overwork an alternator. In any case - full evaluation of the power system is in order.

I’m also wondering what the diagnosis method is.

I’ve seen a real bad battery kill an alternator.

The other thing to consider is the rebuilt alternators. I’ve found there are good rebuilders and bad rebuilders. And it seems to me that places like ADAP and Pep-Boys seem to find a lot more bad rebuilders and good rebuilders.

We have a couple of good independent parts stores around here. There’s a world of difference between many parts they carry and the parts the national chains sell.

First thing is to get your whole electrical system tested. If your alternator is the culprit…then you might consider a local parts store or Nissan OEM alternator.

It might be helpful with diagnosing the problem by knowing which part of your alternator is failing. Could be bearings, one or more of the diodes, voltage regulator, slip ring followers (brushes) worn out, short to ground in the rotor, stator or elsewhere, overheated stator copper windings, broken pigtail or what else can happen?

“The replacement alternators were remanufactured and not purchased from a Nissan dealer.” While I agree with the others that its time to have the system checked and to determine what exactly failed, I have had poor experience with rebuilt alternators other than Delco rebuilds for my GM. Sometimes they don’t even replace the parts but just make sure they are working. You need to know if it had new brushes, diodes, voltage regulator, bearings etc. and not just checked and cleaned up.

You might consider looking for a local auto electric shop which rebuilds alternators and starters in-house. The price would be competitive or better than the mystery replacements you’ve been buying, and almost certainly better quality. Then there’s the bonus: supporting your local economy, establishing a relationship with a local service who you’ll need from time to time, and probably getting some info on what the actual problem was with your alternator which might help you troubleshoot the root problem. I can’t remember the last time I bought an off-the-shelf starter or alternator, except for one which had a defect. Ever since I’ve used shop with does nothing but rebuilds.

All the above comments are spot on. If I had this problem I’d take the car to one of the places that will test the alternator and the battery for free. At the very least have the battery load tested. If it passes the load test, carefully inspect the placement of the battery and the connections that they are not close to touching anything that will ground them out if the car bounced or hits a bump. That can temporarily short the battery out and damage the alternator.

My guess – assuming everything above checks out ok – is bad luck, the “new” alternators have all been bad. I had a similar thing w/a starter motor, the “new” offshore rebuilt one purchased at a retail auto part store chain performed worse than the original. My sol’n was to return the “new” one for a refund (a little dust-up with the store manager ensued, true) anyway once rid of the rebuilt, I took the original to my local auto-electric shop for fixing. I think if I were in the OP’ers shoes, I’d do the same, just take the original OEM unit that came with the car to a local auto-electric shop. Often all that needs to be done is to replace a single diode.

There are a number of reasons why an alternator may not charge and some of those can be intermittent.

I would hope that a proper diagnosis was done on those alternators instead blindly assuming that a no-start or non-charging situation automatically points to a bad alternator. Not always.

Any time there are repeat replacements of the same part involved the diagnosis is suspect; at least by my 2 cents.

The retail auto parts store where I purchased the starter motor, they had a gadget that could bench test it right in the store. Took 5 minutes max. I’ll bet they have a similar gadget that bench tests alternators. That might be another resource. Have the replacement alternator bench tested first. (The auto-electric shop will probably do this too, as part of their repair procedure.)