How many miles does it take to go through Alternator Brushes?

150K

Noticed the Battery Indicator light this morning, so I found a local Automotive Electrical Tech.
He tested the battery, sure enough...low voltage (12.4V).
Battery was recently replaced, so we suspected the alternator.

He pulled the alternator, tested the rectifier and discovered that brushes needed replacement.
Alternator with new brushes are back in the truck, and more importantly Battery indicator light is out

Voltage is about 13.8V, but this is probably due to battery being low.
Will keep an eye on it.

 

Well this guy got over 400k out of his. Mine has 178k (i'm assuming it's original but I got it at 130k). I'd say it's just luck of the draw and you got unlucky! I don't often hear about Tacoma alternators going out.

 

Agree, Luck of the Draw.
Glad it was an easy fix (new brushes).

The tech mentioned that the Rectifier assembly was higher quality vs Hilux alternators.
Apparently Hilux alternators have spot-welded Rectifier assemblies...so they are more difficult to rebuild.

Down South, they never sold 4cyl 4x4 Tacomas...only v6.
They recognize the 2.7motor, as Hilux trucks are everywhere...except they are only 2wd.

 

im more surprised you found somewhere to replace the brushes. most places just replace the whole assembly anymore, lol.

 

Many factors involved in the lifespan of alternator brushes: environmental, electrical load/draw, etc

 

From my pic, you can probably I drive in a dusty environment...lost of dirt roads.

I may pickup a replacement, and keep the original alternator as a spare.
Might also look into an higher output unit while I'm at it

 

If you just let it idle in your driveway you can go through an alternator in exactly 0 miles.