What is the lower hose of the radiator do and what fluid runs thru it? Mine leak

Hi, my name is Devin. I am an auto repair expert with the Car Genius team here at RepairPal. I’m sorry to hear you're having trouble with your Forester. The large lower radiator hose carries coolant from the radiator back to the engine to help regulate temperature. There are also smaller diameter hoses that carry transmission fluid to and from the transmission. If the fluid has a reddish tint and an oily feel, it is likely transmission fluid. Since the leak is getting worse, I'd recommend having the leak diagnosed to prevent further damage. If you need more advice, have any other questions about your vehicle, or would like to get connected to a RepairPal Certified shop near you, we have you covered. Give us a call at 877-913-1554, and we will happily help you out!