hey guys, when does the alternator usually go out on a 3.4 v6 tacoma?..

 

when your in the middle of nowhere all alone

 

hahahah exactly what i was thinking thats why i wanted to kind of get an idea on about when this will happen mileage wise

 

The humorous response of the previous post is the cute way of saying that, technically speaking, the half-life of an alternator varies so widely, that it is meaningless to use the median as "the usual".

In normal-speak, its simple. You will find alternators that last a very long time, and others that fail early. And, one can "cause" an alternator to fail early if you work at it.

So the real question is, what makes you think the alternator is bad?

Also note, many shot-gun artists will tell you the alternator was bad, when it was a $0.2 fuse.

 

On a side note, would a failing alternator drain your battery if the truck isn't started for just a day or two?

 

Theoretically, yes. Probably, no. Very very unlikely.

 

mine went @131k, but i think i helped with a bit of muddy water

 

Then I most likely have a slow drain somewhere... crap. I hate troubleshooting stuff like this. Takes so long.

 

Oh its fun if you have plenty of time. Otherwise its a pain, as you say.

Knowing how to use a DVM is a very big help. And an FSM.

 

What is a DVM and a FSM? How do you use them?

 

Digital Voltage Meter (or Multi-meter)

Factory Service Manual (2 volume set)

 

+1

 

Mine went out at about 83000 miles.. . . probably because I went through a really deep mud hole that came over the hood though.. .

 

Mine went at 230K, didn't know anything about cars at the time, went with stock replacement, been pissed off about lack of amps since.

 

Mine went on Pritchett Canyon on yellow hill - halfway up at 10:00 PM after running my winch, PIAA's and rocklights for 30 minutes up rocker knocker, Hmm I wonder why?

(I got Boyle technologies in CA to rebuild mine for $125 and it went from 60 AMPS at Idle to about 130... It has been bomb proof since!)

 

I have both of these... so how do I track down the "leak"?

 

First thing to do is check the voltage on the posts of the battery with the vehicle off. Should be around 12.2-12.8v

If so, turn the vehicle on, check voltage again at the posts. Should be 13.9v or greater at idle. If not, rev the engine a tad and see if you get the proper voltage. While you are at it, check voltage at the clamps. Should be almost identical to the voltage you read at the posts.

 

You could just have a dieing battery. How old is it? I've had a couple batteries have the same symptoms as you. Car would start fine but if I didn't drive the car for a couple days the battery would be dead. When they get old they just won't hold a charge any more.

In both cases I replaced the battery and all was well again.

 

IIRC you have alot of accesories. check all the grounds and connections first.
look for voltage when things are supposed to be off.

 

Would it be possible to confuse a bad alternator ground for a bad alternator, fuse or battery? Would increasing the size, or guage of ground wiring on both the battery and alternator reduce drops in power under say, 1000RPM?