this semi tractor, had just left the mntc shop for brake service. the right rear ABS link was left off of the vacuum booster, the Traffic Investigator said the truck did exactly what a 3 brake vehicle would w/o the right rear wheel providing any braking action... it went 90 degrees to the left and merged me into the Media wall. 8 days in ICU, 15 days in Recovery, six months in Therapy/Recovery 3 concussions.