'semi  indefinitely in my experience.
though, quality of rebuilt units varies.
I always and only use Bosch rebuilt alternators,
and I also carry a spare good used one on long trips.
as well as a spare 'brush package/voltage regulator' unit too.

----- Original Message -----
From: "azsun99" <azsun99@EARTHLINK.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, February 07, 2009 10:47 AM
Subject: alternator lifespan

> In light of Loren's experience, what is the approximate life span of a
> late model
> alternator, it's brushes and regulator, assuming the belt is properly
> tensioned and
> the van doesn't see a lot of time on dusty roads or in other adverse
> conditions?
>
> Jerry