One problem related to power train driveline has been reported for the 2008 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Toyota Sienna based on all problems reported for the 2008 Sienna.
2008 Toyota Sienna 3. 5 v6 has had piston slap since new. Toyota knows that there is a flaw in all of these engines but because there have been no failures and few complaints , they are choosing to do nothing about it. I like engines and I know that where there is noise there is excessive wear and potential future failure.