I have an 01' X5. 4.4 with 275,000 miles and counting. It has the original motor and trans. I replaced the original water pump at 260,000 I just replaced the radiator 3 weeks ago, and now I have to repair the driver side cv boot this week. I love my X5 and am very happy with it. I only run synthetic oil from BMW in it and change the oil every 15,000 miles. When I change the oil I'm only at about 1/2 quart low not bad for an engine with 275,000 miles