"WHAT THE HELL ARE YOU DOING?!"
Well, this is certainly one of the most pants-shitting close calls I've ever seen on the road, followed by one of the most harrowing screams I've ever heard. I can't believe this didn't end in a head-on collision.
CBC News reports that the crash occurred on Ontario's Highway 11, way up past Nipigon. In the comments section, the YouTube uploader claims to be the screaming offended truck driver's wife and states that the other driver didn't even stop after running her husband off the road. She says she is trying to find the identity of the other trucker and keep him off the road. Ontario police are still investigating the crash.
(Hat tip to Rob!)