My S80 has 65K miles. I have on oil leak somewhere because my oil level is constantly low and I have to keep adding oil.

I obviously have to get it checked out but the two symptons I have noticed are oil leaking around the oil filler cap and smoke coming out of the dipstick tube after the car has been idling for a while. The oil on the dipstick seems normal though (i.e. no sludge or anything like that).

Is this most likely a clogged breather valve/breather box? I have been consistent with my oil changes (every 3K to 4K miles) and my mechanic uses Castrol GTX, so I would be a little curious as to why the breather valve would be clogged at 65K.

Could the smoke from the dipstick and leaks around the oil cap be indicative of any other type of problem?

Thanks in advance for your help.

 

Sounds like something in the vent system is clogged.
There is a hose or fitting on the intake that will get clogged and act like this.