This is a picture of the most common Subaru engine, the 2.5 liter 4 cylinder. This engine can be found in all 2000-2010 Subaru Outbacks, Legacys, Impreszas, and Foresters, and later on some models. If your car is a turbo or an H6 a lot of these principals will be the same but the costs are higher.
This particular engine came from a 2006 Impreza & has some updates, but nothing that will concern us for this posting.
The suggested interval for Subarus timing belt replacement is every 105,000 miles. People call us and ask “How much does it cost to do this job?”IF… we JUST replace the timing belt by itself, it’s just under $400.00.
BUT…. notice all those pulleys that belt goes around? They have all been spinning at the same RPM as the engine, for the same 105,000 miles. Those pulleys should be replaced at the same time.
OK, Back to the full frontal view. Note the larger pulleys at the outer edge of the engine. These are the camshaft pulleys. Their job is to open & close the intake & exhaust valves to let in the air / fuel mixture in & the exhaust gases out in precise timing with the center pulley that drives them. Behind each of these are oil seals that we would replace at the same time as the other pulleys, water pump, & timing belt. This assures that you wont have to spend the money to replace any one item 6 months or even a year down the road. If you spend the $1000.00+ to do this job right, you will get another 105,000 miles out of your next timing belt trouble free.
NOTE; If your timing belt does fail, major engine damage will send this repair close to $3,000.00. The math is pretty simple, you get what you pay for.