I'll add to the story, since I've driven on that deathtrap of a highway many times.
It sucks... It's 2 lanes and narrow. It's HEAVILY traffic'ed it connects detroit to chicago (and therefore canada to chicago)... LOTS of semis.
The speed limit for cars in michigan is 70, but trucks is 60. A car can travel 84 without being pulled over (or 79 if you REALLY want to be safe). Many truckers have systems in their cabin that do not ALLOW them to go over the speed limit... So you have a very unsafe situation in heavy traffic where cars are passing semis that are virtually standing still... and then some idiot fucking car will brake behind a semi, slowing down to 60... and then pulling out into the left lane where a line of cars could be going 84... PLUS the trucks that pass each other it creates a traffic jam EVERY SINGLE TIME, because of the speed differentials. So chunky traffic conditions cause more and more congestion..., it snowballs...
It's a totally shitty stretch of freeway, the roads are in terrible shape, I'd name it the worst freeway in the u.s. and I've driven all over the country.