Ok, so I pulled out my Bentley Publishers BMW X5 Service manual, and found a big note in the section on Front Suspension as follows: NOTE Steering wheel vibration during braking (usually at road speeds of 50 to 60 mph) are often caused by faulty suspension arm bushings, not out-of-true brake rotors.

It looks like this was written for me . I will check out the suspension. Looks like my rotor lateral runout can be eliminated.

Thanks for pointing me back to check the manual.