I've got a small leak in my transmission coolant hose (P/N 108493) and I'm having a pretty difficult time getting the fitting loose at the water pipe connection. The fitting on the transmission loosened up relatively easy, but the one on the water pipe won't budge. I've used PB blaster, WD40 rust release penetrant, etc. - it doesn't want to budge. I could probably get it IF I took the water coolant pipe out of the car, but that involves draining the coolant, and I really don't want to do that if I don't have to. Any suggestions