Five alternators? Really??

I didn't think so either, but it happened...

 

now that I'm thinking more about what else could be drawing more power than necessary, I do have aftermarket tail lights and I usually drive with the driving lights on all the time. does anybody think that maybe my tail lights draw too much power and the fact that I use them all the time adds to the problem?

 

If you want your truck to last, buy only OEM parts. Aftermarket, especially from the discount stores, usually are not as good as OEM. Do you have any big stereo equipment (amps)? That will cook them. Or if you run your battery down with the motor off frequently then that can shorten the alternator life. As mentioned above, a weak or failing battery can overheat the alternator. Did you make any other electrical changes just before they started failing? Add big lights, or any other big draws?

My OEM alternator lasted about 175k miles. I tried to buy a new Toyota alternator, but our trucks are so old now that Toyota only sells remanufactured units. But it looks and works like new. Only about 10k miles on it so far, but it works.

 

I drive with lights on all the time no issues here, not sure about the add ons...

 

Hell no. Stock alt should be able to handle up to 80amps continuous. Your taillights and headlights are drawing a fraction of that.

 

can i paste a link?

http://www.carid.com/2003-toyota-tacoma-taillights/ipcw-euro-tail-lights-262537.html

those are the tail lights I have. The radio is just a pioneer radio with bluetooth, nothing special, no amps or anything like that. There are no other add-on items of any kind. I don't think there's anything wrong with the tail lights or the radio since plenty of people put on extra lights and add amps and things to their vehicles without problems. I'd say that just maybe there's the potential for bad wiring in one of those areas but I feel like that's unlikely...

 

OP, where abouts are you? Shoot me a PM if you don't want to share in public.

Have you had the failed alternators tested? A reputable shop should be able to tell you what the failure was, not just that it's bad. What's the voltage across the battery terminals when the truck is idling? Battery voltage when the truck is off? What kind of battery are you running?

 

OP get one from the dealer and chech you battery, toyota's are picky about their parts, i was cheap and bought aftermarket catalytic converters for my Avalon in GA for emissions testing, they kept failing until i got one from the dealer

 

I'm in Connecticut. Yeah apparently I have to get more serious about these alternators and stop relying on whatever kid is working behind the counter at the local parts store. After I put the new alt in the voltage across the battery terminals while idling was around 14.2. After I turned the truck off I watched the volts settle down around the low 13's and then I stopped watching. I need to take a moment and do some serious voltage testing to get good numbers. It's an Interstate battery

 

Do a load pull on the battery. Just checking volts isnt going to tell you crap.

 

I turned on everything i could (radio, high beams, heat fan on high) and the voltage only dropped to about 13.6

 

I mean take it to a shop and have them test it with a load. Not saying its the battery but just to rule it out.

 

Yeah, I've got to have someone good take a look at it. Not a lot of options for good mechanics in my area that I know of... more research to do...

 

Next bad alternator, find out what component failed in the alternator. Oreilly's gave me a printout when diagnosing a problem with wife's ES350. See printout below as a sample. (My problem turned out to be sticking brushes.)

I doubt you have a high parasitic draw; otherwise, your battery would drain out. You can check anyways to rule that out. Excessive drain is considered over 50 mA. See link below for details on how to set up, or look for Eric the Car Guy videos on youtube.
http://www.aa1car.com/library/battery_runs_down.htm

 

Thanks Chuy, I'll have to go to O'Reilly's and get a print out. And I'll check that link when I get home

 

I didn't read all the replies but I had a buddy go thru like 4 Napa reman I'm 6 months. Then he got the Napa new with lifetime warranty lasted 2 years till he sold the truck.
Moral is there is a big quality difference in alts. So there may be nothing else wrong with ur truck. There wasn't working his.

 

Brushes, cheap PM for that OEM Denso alt.

 

I must be the exception; I've rarely had problems with reman's from AZ, Pep Boys, etc... The OReilly's alt I mentioned above is the first one. It had sticking alt brushes but since the problem could not be reproduced on the bench, they could not honor their warranty. It's a little annoying but I see their point. They said if problem re-occurs, take veh to them so they can test with veh running. Had I known that before removing the alt ...

The other option is to have a local electric shop provide their reman alt. Prices may be competitive with auto chains and they are more knowledgeable - they may troubleshoot your problem.

 

The quality of rebuilt electrical parts has really gone down hill and seems to get worse.

I would think 5 bad alternators is quite possible but other problems could very well be present

I have 200,000 miles on my original alternator but all my battery cables are upgraded

Maybe my older alternators late nineties are different but my brushes came attached to the holder no soldering

 

If you still have a problem, this site has some good basic info on alternators and how to work on them. They also sell higher output units.

https://alternatorparts.com/

Ran across it while looking for a new higher output alternator for my 85