There several other rear suspension components such as tie rods that can cause the 15 degree lean, especially if something is bent. Did you have an alignment done after you replaced the ball joints and upper control arms? It is typical that the full suspension rebuild is due not that far beyond 80,000 miles.

I wouldn't be buying a ABS sensors without more troubleshooting. One reason many owners feel a X5 maintenance costs so much is they try to find a problem by replacing parts rather than spending enough troubleshooting time to pinpoint the root cause.

A bad wheel bearing will usually generate a grinding sound when turning one way or the other. I wouldn't replace a bearing or a strut until you have a much better idea where it is coming from.

I can't imagine what has caused the rotors to be that hard to remove. Have never seen a rotor that wouldn't come off with some PB blaster and a big hammer.

To address the low idle without spending many $$$. Pull the dipstick or the oil fill cover and with the X at an idle cover the hole with a piece from a garbage bag. CCV not working properly can mess with idle. If the CCV is working properly there should be vacuum that will pull the plastic in. Next check to see if the air filter needs replacement--just remove it and see if it runs better. Next check--disconnect the power to the MAF and see if the idle changes. If it doesn't remove the MAF and clean it with MAF spray--don't skimp on the spray and be sure to spray all the wire including the ones rather hidden.

Have you load tested the battery and monitored the alternator output? BMWs are sensitive to out of spec voltage which can cause a variety of strange lights. Also, I have caused ABS DSC lights to come on after working on the suspension. Cause was the level sensor links were turned toward the inside rather than toward the outside of the X-- though I also get an air suspension inactive error as well.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas