Things to Watch for if Your X is Around 50K
 

I have a 2002 X5 4.4L with little only 50k miles, my battery went dead 2 days ago, no warning, just wouldn't start in the evening. The car started just fine in the morning and afternoon. So if your X is around 50K use a volt meter and check the battery often. Anything lower than 12 volt with engine off, you should keep an eye on things. Anyway, I was in the parking lot and looking for a jumb, one thing led to another, the expansion tank pipe broke. Yes the little one on top of the expansion tank, that suppose to be made out of metal but BMW decided to save a buck and made it out of plastic instead. Well guys if your X is around 50k you may want to check it also. It get harden with heat and age, all it took was a little push and it broke in half, and when I picked it up to check it, it broke into 1/3. Nice huh? It is a regular stock item for my dealer, and he stocks a few of them too, that should tell you something about those pipe. Back to the battery, I got a replacement from Sams Club today, it is the Type 94 with 850 amp. It is $65, lowest I could find anyway. Here is the kicker, the Sams' battery book didn't list a battery replacement for the X, but it fit my X just fine. Don't forget there is a vent hose that comes with the battery, you will need it. The first battery I picked up didn't have one, the second one did. Also, my car die at idle and low engine speed during test drive. I thought something else was borken. Well after the test drive I stablized the idle speed with my foot and let it idle for about 15 minutes the problem went away. So if it happerns to you after you replace the battery, try idling it for 15 minutes. I guess the computer have to reset the value of the senors or something.
For the longest time I thought German auto engineering is the best in the world, i didn't realize how wrong i was until I do my own repair on them. I guess engineering greatest vs. bottom line, bottom line always win.

The list for 50K is VERY long. Do a search and you'll find a lot of other things you may want to change proactively before catastrophic failure.

hi zulu, what's the key word i should use to do a search for that long list you're talking about?

thanks in advance...im creeping up to that 50k myself

"common failures" "water pump failure" "CV Joint boots" should get you started.
We had a thread running a couple of months ago that listed just about everything that people have replaced on or before 50K. Frightening list if you are swinging by your own tail.

75k up from new

New Battery, brake rotors, oil cooler and replacment for MkIII sat nav
Cosmetically inner door handle trims and that's my lot

Guess I'd better be ready....

German made - I stand to be corrected but aren't US X5's made in the US??

Cj,
Get to your waterpump soon. They fail from 30k on and at least one person here cracked a head when it went.
I had WP, t'stat/t'stat housing and belts replaced at 38k when I first noticed slight water dripping from the "tell-tale" on the pump. I'm getting to 50k and starting to think about a new race ready pump that is much better made than OEM.

Yes, but they are German trained South Carolinian's. ;)

This reminds me to ask the dealer to look at my water pump again to see if it has been replaced. I tried asking him before, but guess he forgot. Ughh..

Regular manitainance goes a long way...as you tried your hardest to find a cheap battery at sams club witch will last probably less then a third the life of an optima red top at $120 I am guessing preventitive maintianance like coolant flushes and things were passed on as well...pay for it now or pay for it later kids.

another fun one is the window regulator problem; quite costly too.

Window reg, front CV already replaced at 40k. I didn't say German made, just German engineering. Never had a car that have that many parts break at that early in life. I think this is going to be my last BMW for a long time. Spent more time working on this car than when I had my Fiat.