All very good points. IIRC, the warranty period for the drive train is 50,000 miles. You might consider synthetics and performing your own changes after the warranty period is over if you are concerned about voiding your warranty.

I have owned Hondas, Acuras, Subarus and now my first Toyota. I have put on between 100 and 250K on all except for the Prius which is at 47K. I have never had a problem other than normal wearing items such as brakes or clutches (which wouldn't be convered by the warranty anyway) in any of them. Thats why I don't get too concerned about voiding the warranty. But obviously my view is biased by the fact that I have never been burned. Lets hope I continue my streak with the Prius.

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