Could be a characteristic of the X5 engine cooling system. There is a lot of air circulating around the block. Thermostat settings could impact it. We are speaking here about how the vehicle stands up to misuse, however. Give it a good drive once a week. It simply wasn't designed to never be warmed up. If you can't warm it up properly, then change the oil a lot more frequently (as per the severe service recommendations), and clean out the CCV each season.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue