Originally Posted by Skippy

Just in case anyone reading this has the unsettling experience of losing vacuum assist while driving, the brakes will still stop the car. You just have to press the pedal A LOT harder than normal. I experienced this first hand when the vacuum pump on my 240D failed. I got to drive around San Diego for a few days with no power brakes until I scored a used vacuum pump from a junkyard.

For additional fun, I found out after installing the pump, that it interfered with the power steering belt, so I had the other fun experience of getting to drive with power brakes but no power steering until I had the parts and time to repair the original pump. This included driving it from San Diego to Carson City. Actually not bad once rolling, but parking lots were a hundin.