Here's a tip on the Axle's/boots in the front. NO U-Turns ESPECIALLY on cold days. Turning the wheel completely puts a tremendous amount of stress on the boots. Before you know it you will get the noise/vibrations when on the accelerator. I found out the hard way, since I didn't have to worry about this with my RWD 323I. If you keep from turning your wheel/sterring wheel to the max you will not have to worry about replaces those axles/boots on the AWD XI.
I purchased my 2002 330xi November 2009 w/110,000 miles on the clock mint condition. Rough roads and winter in the northeast cost me a lot in BS repairs. The car now has about 144,00 miles on it.
List of repairs not including Inspection I + II things. Coolant reservoir/expansion tank replacement, 2 rear strut mounts, 2 rear struts, 2 rear springs, 2 Front Axles, 2 Front Lower Control arm bushing, Valve Cover Gasket set, Valve cover (actual cover was cracked), Fan Clutch, DISA Flap (aka Adjuster Unit), 4 Oxygen Sensors, 6 Bosch Plugs, Electronic thermostat, 6 new tires (I bought 4 and less than a week later a pothole blew out entire right side, 2 days prior to the blowout a nj state trooper slammed on the brakes and smoked his tires in front of me causing me to do the same on the new tires, which caused a small flat spot in the tires!!!)
Again the suspension work was do to the extremely harsh winter and roads of the NY/NJ area. After I get this 330xi fixed (was rear ended on a hit and run), at the end of the summer I'm going to do engine mounts, and tranny mounts. My driver side lock actuator is shot, but I have two remote FOB's so the hell with fixing that. All in all its a awesome good performing car.