Something goes good with with the wheel off because it acts as.it.should and goes bad when the wheel is on. I suspect a connection for brake sensor opens when you hang the wheel on? I would play wheel on and wheel off and look at stress on sensor connection. Should have to tighten lugs? Something electrical-signal changes with the wheel present and you must find that.

I am paying interested attention here because I bought a 07 x5 this month and I see it's service computer says I need to do both front and back brakes in under 5000 miles. Curious it has been saying exactly the same miles for the almost 3000 miles I have driven it. Will be checking pads maybe today.