How long are the batteries in my 2006 Toyota Prius likely to last?

I have a 2006 Toyota Prius with which I have been very pleased. It is approaching four years old, half the guaranteed battery life, and I wondered if you have any evidence of when Prius batteries tend to fail. Should I be considering replacing the car now, or should I wait until just before the price begins to plummet as the 8-year point approaches? When do you think that might be?

Asked on 10 October 2010 by DH, Galashiels

Answered by Honest John
I can’t tell you. There are still plenty of Mk 1 Prius driving about. The extremely good news is that Toyota is seeing Prius IIs used as taxis with over 400,000 miles on them. They are exceptionally reliable, have a very gentle powertrain, and less to go wrong than a conventional car. They actually make a very good secondhand buy.
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Much better than the original. An enjoyable, practical, safe, economical hybrid. Looks good, too. Prius Taxis have run to 400,000 miles plus with very little trouble.

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