I don't know if this applies to your 740, but many years ago, my 164 was
making very similar noises just before the driver's side lower ball
joint separated and dropped the suspension onto the pavement. It was
making a creaking noise when steering and the boing when stopping. The
creak was the dry ball joint and the boing was the spring shifting
slightly due to the looseness in the suspension. I know that your car
has a completely different suspension, but if it were me I would check
ALL the suspension components NOW. It was no fun jacking it up and
replacing the ball joint on the side of the road, and I'm just glad mine
let go pulling away from a stop and not on the interstate
