One problem related to radiator has been reported for the 2007 Subaru Forester. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2007 Subaru Forester based on all problems reported for the 2007 Forester.
Blown head gasket. 2007 Subaru Forester 2. 5xt. 54k miles. Problem presented itself violently as I was driving on freeway. Suddenly engine temp-gauge fluctuates and starts to rise. Pull over, coolant is forcefully exiting overflow tank. Shut car down, temp gauge drops quickly. No external signs of leaking coolant with subsequent refill and testing. After coolant warms up (3 minutes idle) coolant begins to voilently exit radiator cap (when off) or overflow tank. Exhaust very sooty. Shakes my confidence in Subaru and their engineering to have a head gasket blow this early. Subaru coolant conditioner is a re-branded stop-leak. Was looking at the new brz, now I will not be buying and do not recommend Subaru unless manufacturer acknowledges and makes an effort to remedy the situation.