One problem related to radiator 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.
While driving home the oil line running from the oil cooler on the radiator exploded. Oil was sent over the entire engine compartment and dripped over the road leaving a trail the block left going to my house. The hot oil spraying over the hot engine was a danger to catching the van and the garage it was parked in on fire. This is an extremely dangerous problem that Toyota is aware of yet has not issued a recall for these vehicles. I was lucky that this happened so close to my home.