I will soon be purchasing an X5 (used) and I am trying to decide what the differences are between the 01's, 02's & 03's - I have a '95 325 and I didn't really notice until after I purchased it that the flat black trim at the bottom changed to be the same as the body color in '96. I am looking to see if anyone can point me to some subtle differences like this in the X5's - The older ones seem lower, are they? did they use smaller wheels?

One of the main differences is the xDrive system. The new one is far superior, since it adjusts the power given to each wheel. Other than that, obviously the subtle yet effective exterior touches like the angel eyes and wheels.

As for being lower, I don't think so. But I'm not positive.

xDrive is nice, but I think valvetronic is a big difference. MY00-03 get crappy gas mileage, around 13-16. MY04+ get close to 20.

xDrive is nice, but I think valvetronic is a big difference. MY00-03 get crappy gas mileage, around 13-16. MY04+ get close to 20.

You're right. Good call on that bud.

In 04 there was also a facelift, new headlight and bumper designs on all X5's. However the 3.0 still has the same engine as the previous years.

01 to 03 the same, 04 on X-drive, face lift ( bumper angel eyes ) & valve tronic.
different heights may be due to pakages IE sports and adjustable suspension which were available on all years I believe
wheel sizes range from 17 to 19 on regular models and the (is) models getting 20's
interiors are pretty much the same and all the models have the black plastic lower mouldings due to it being an SAV
Hope that Helps
BigFish
Oh yeah on the 04 & up 4.4 it has roughly 30 extra HP