dilemma

[alpac]

Here is my dilemma. I have been contemplating selling my 2000 X5 4.4 which has now 110k miles on it. I bought it 7 years ago, paid it full on day one and have been enjoying it since. It still looks really nice inside and outside and if I sell it I will be lucky to get 10k for it if I am selling it myself. The dealer I bought the X5 from and which maintained the car under the extended warranty is offering me $8600 for it even if I do not buy another car from there. I have 2 other cars and 2 bikes and I am single since my divorce therefore I do not drive the X5 very often. If I was selling it I would not replace it immediately but may be sometime next year with a good 2 to 3 years old car. I doubt that I will go for another X5 but rather a 330 or 530 if it was a BMW.

I had my share of problems and issues, actually more than on any of my other cars, but most of them happened under the extended warranty which expired more than a year ago. During the warranty I had the following repairs done:
CV joints were replaced, Valve cover gaskets, Oil separator, Steering rack, 2 windows regulators, FSR, etc… I am mechanically inclined and since the warranty expired I have been able so far to fix myself everything that needed to be fixed which includes solving the engine code issue by changing the MAF and O2 sensors, replacing control arms and ball joints, one windows relulator, AC issue (high pressure valve needed to be replaced), and a couple of other things. There is still a clunking noise which I cannot locate the source and I may have to bring it to an good independent BMW specialist I know for that. Now my main concern is a recent short squeaking noise between gears under strong acceleration mostly when the car is cold. It sounds like the noise of a belt slipping on a pulley. Other than that the car drives beautifully and the tranny is still very smooth. The reason I am thinking about may be selling it is mainly because of this squeaking noise from the tranny and possible other big issue in the future.
On the other hand I know my X5 very well now, I know what has been replaced, I can do a lot of things myself and it is still a very nice car to drive. If I buy a similar (similar in term of driving pleasure)a pre-own car I will have to add at least another 18/20k. I test drove a 3 years old Audi A6 3.0 with 40k miles at the dealer this week and although it is a nice car it is no X5. Amazingly enough for such an heavy vehicle my X5 feels more responsive than the Audi. So I am puzzled, should I sell it or keep it? not sure I just wanted to share my thoughts with the community here.