The 3RZ is a good motor. A good replacement for the venerable 22R/22RE series motors. They use a timing chain instead of a belt and the cams are gear driven. There's no reason not expect nearly as much longevity as the prior motor. When looking at used Tacomas I've seen mileages anywhere from 150,000 to over 250,000 miles on the original motors. I'm sure some go even longer.

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