Straight-Line Reversal – The opening challenge has all three contestants in the same car as they attempt to reverse in a straight line through a straight hallway in 20 seconds or less; contestants have ten attempts to do the challenge before failing it outright. The challenge car is the 1967 Chrysler Newport used in the parallel parking challenge. Aaron volunteers to go first, but in his first attempt he barely goes one car length before his 20 seconds expire, and he finishes his first attempt in five minutes after hitting things. Aaron is distracted by Sly in most of the rest of his attempts, and is unable to finish. Shirley passes on her first attempt after 19 seconds. Sly collides with many of the obstacles in a horrific manner in each of his first eight attempts, only stabilizing somewhat in his last two; nevertheless, he still hits things, and is unable to finish in 10 attempts.
Challenger Challenge: The Mega-Challenge – The annual challenge begins with a 50 km/h slalom, before dropping to 40 km/h into an icy corner, and then through a forward obstacle course, into a doughnut, through another obstacle course in both forward and reverse. The drivers must then go through an Eye of the Needle in reverse, before finishing with a reverse flick. Aaron fails the slalom by taking the turns too wide, and is a little late in the icy corner (though he does not hit the wall, he does go off of the course in making the turn). He has no significant problems in any of the obstacle courses or the reverse Eye of the Needle (though he fails the doughnut), and makes his reverse flick attempt too early. In his run, Sly goes too fast in the slalom, and goes off the course entirely. He recovers in time to attempt the icy corner, but goes through the wall. His doughnut attempt is not shown, but he collides with things in both the forward and reverse obstacles. His reverse Eye of the Needle goes well, up until hitting the last arch. He is unable to properly perform the reverse flick. Shirley, in her run, does a flawless slalom and nearly makes the icy corner while going at 50 km/h. She turns in the opposite direction too early in the doughnut, and does not hit anything in the obstacle courses; the rest of her hits in her run were all from hitting the arches in the reverse Eye of the Needle. She finishes by performing a perfect reverse flick.
The Road Test – The annual road test takes place on the streets of Hamilton, Ontario, but the Challenger is no longer road-worthy. Instead, the final drive will be taken in a 1966 Ford Mustang convertible. Shirley is confused through the streets of Hamilton, with a particular trouble in dual-turn lanes (intending to turn in the outside turn lane but eventually going straight through) and stopping in pedestrian crosswalks (which she does throughout her run). She is even caught going down the wrong way down both a one-way street in front of a police vehicle and a two-way street up a blind hill. When trying to merge on a highway, she stops in the merge lane, and once she gets into the middle lane of the highway, she goes too slow - so much so that she is unable to make her exit due to traffic on both adjacent lanes going faster. Her run finishes with 26 moving violations totaling $2860 in fines. Sly is ultimately confused by trying to find the right turn, and on numerous occasions, he stops in the middle of the intersection trying to read the crossing street signs. There were no major incidents once on the highway, and Sly even reflects on his own driving behaviour after a passing driver tries to take a picture of their car with a cell phone. In Aaron's run, he starts by running through a stop sign (ironic as it was ultimately the cause of his hospitalization six years ago), and his composure comes crashing down when a police car suddenly blares its siren behind him. However, as the police car passes by, his driving becomes much better, with no problems in the rest of his run. The run earns a round of applause from the experts.
After the six nominators and contestants give a somber farewell to the Challenger (complete with a mock funeral ceremony), the four experts give their final opinion of the contestants. Sly admits that the road test was more comfortable than any of the challenges, but he was ultimately on edge through the test. The opposite happened for Shirley: good challenge performances but horrible road test. Aaron admits that after the road test, he finally got everything and more out of rehab. Philippe and Peter believe Sly is Canada's Worst Driver due to his performance in the challenges, but Cam and Andrew believe that Shirley's performance in the road test makes her Canada's Worst Driver. Shyamala therefore has the deciding vote.
As none of the experts believe Aaron is Canada's Worst Driver, Aaron is named the final graduate of the Driver Rehabilitation Centre. Ultimately, Sly is considered to be able to drive away on his own, while Shirley wasn't, and that's why she is ultimately named Canada's Worst Driver. Despite Sly avoiding being named the worst, Andrew tells him that he has absolutely nothing to be proud about, and Fred says that Sly simply got lucky that Shirley happened to do worse in the Road Test. Shirley still leaves with parting words of encouragement from Andrew, who implores her to continue driving, and as a special mark of respect for her doing so well despite ultimately being named the worst, Andrew allows Janis to drive Shirley home, instead of the usual final humiliation of being forced to catch a plane home while her car is towed to her hometown.