2005 X5 3.0i sport 120K miles

I normally don't keep my cars for too long but something about my X5, I am not getting tired of it and want to keep it forever. FYI, I bought it new and it drove beautifully for about 7 years. Maintenance's done regularly and it's kept in the garage so still looks glossy. But in the last 3 years or so, mechanical problems started to appear.

- Had to get hoses, fittings, pcv replaced after serious oil leak during arctic winter

- Another minor oil leak, gasket replaced

- Coolant sensor and thermostat replaced

- Rear door carrier replaced

- Wear and tear items like CV boots, window regulator, wheel camber, etc... all corrected

What other costly problems may be knocking at my door soon? What to do prevent costly repairs? Many people have been telling me it's time to sell it while it still have some trade in value. Because of it, I'm kind of afraid to take it for a long trip.

What to do? Chicago winter scares me and this car isn't quite built to battle it IMHO.