There is an admitted defect in the design of the 1999-2001 Toyota Sienna and Camry engines. The cooling chamber passages to the cylinders were reduced in size to reduce hazardous emissions which had the unanticipated side effect of causing the temperature of the cylinder heads to reach up to 130 degrees. For many owners, this has caused the oil to oxidize forming a sludge in the engine which in our case led to engine failure in our 2000 Toyota Sienna van requiring engine replacement at 59,000 miles costing over $8,000. The same situation occurred with our 1999 Camry. Toyota claims that this is due to not changing the oil frequently enough, and this may be true. However my brother's friend bought a Toyota Celica back in the 1970's and never changed the oil, never even opened the hood to add oil or maintenance it at all - just drove it until quit - at 80,000 miles. Granted this is not advisable but evidence suggests that while less than optimal oil change frequencies may contribute to this engine failure problem in the 1999-2001 models, based on other research I have read with other owners having the same problem leading to engine failure in these models even with mileages as low as 29,000 miles, I don't buy Toyota's argument. We owned 3 Toyota's at the time, 2 Camry and 1 Sienna. Because Toyota did not own up to this design defect and reimburse owners for the damage caused by their flawed engine design without their providing oil change receipts - (e.g. what if you don't save receipts and/or what if you change your oil yourself)? - for this reason I will never buy another Toyota. I own a Subaru WRX and am planning to purchase another Subaru soon.

- Kaneohe, HI, USA