So yesterday, I took my '06 MCS in for scheduled maintenance and the dealer changed the oil and flushed the brakes. After I drove off, I heard a thump and what sounded like I had run over a piece of metal, like a bolt or something. I looked behind me and saw nothing in the road.

During the commute this morning, when I hit a seam in the road, I heard what sounded like a spring snapping and a thump from the rear of the car, as if something had broken and fallen off of the car. Again, I didn't see anything behind me in the road.

Is it possible that the service technicians didn't reattach something properly? I'm going to put it up on the lift later today and check things out.

 

did they maybe leave a wrench or hose/bleed container attached???

 

If they flushed the brakes, the were definitely working at the back of the car, but there would be no reason to take any major parts off and then fail to install them correctly. Like chadtoolio says, it might have been a tool but why would it still be making noise if it fell off? Back to the dealer, post haste!
-skip-

 

It didn't make any noise after the initial sproing-rattle-bang.

 

I put it up on a lift and went over it with a fine tooth comb. Found nothing out of the ordinary. I suspect that I just ran over some odd bit in the road.