I have a question with regard to omissions in the coolant carrying hoses. The two main radiator hoses are always mentioned to replace, but the heater core hoses and hose #5 in the diagram are never included. Come to think about it, I've never seen a mention on more than one e46 board of anyone ever having one of these hoses fail? Anyone?
And if I wanted to prophylactically replace the heater core hoses, are they not connected in impossible to reach locations?
I know the large hoses are under more stress, and smaller hoses can stand up to higher pressures more easily, but eventually all rubber will wear out. I'd like to hear from anyone who has already replaced these as preventative maintenance.
(or otherwise for that matter?)