Gaffes

Sheriff Bud Boomer (John Candy) and friends are driving a commandeered garbage truck, and are stopped by a Canadian motorcycle cop (Dan Ackroyd). In a hilarious scene, the officer insists they reiterate all the derisive spray-painted graffiti with the French equivalent, since Canada is bilingual. Once they're back on the road, "USA all the way" (on the front bumper) is missing the French version. Later, when the truck arrives in Toronto, it is there.

Sheriff Boomer sprays French translations onto the side of his truck. In the next shot, the truck has only English.

When Honey is making the CN Tower out of mashed potatoes, the antenna disappears from the top between shots.

When they approach the dock and look out, the river is calm, when they leave in the boat, the water is very rough out and large waves.

The boat they approach at the dock has a Johnson outboard motor, when they leave the dock the outboard is a Chrysler outboard motor.

The helicopter that brings the Russian president to the White House has U.S. markings on the side, and a Canadian registration number on the belly. U.S. registrations begin with N, Canadian ones begin with C.

In the campfire scene, Boomer, Roy Boy and Kabral are discussing movies and the recurring plot element about the fact that 'the black guy dies' and they mention several examples like Jurassic Park, Unforgiven, The Dirty Dozen, Witness and Alien. The problem with those examples (although accurate in this sense) is the fact Kabral says that the black guy always dies first, and in those movies they're not the first ones to die. However, he got it right with The Shining and Forrest Gump.

Leslie Nielsen's name in the list of prominent Canadians is misspelled as Nielson.

The sign in the CN Tower states that there are 10,000 steps to the top. There are actually 1,776 steps.

In the movie the Mounties, wearing red uniforms, are on patrol in Niagra Falls, but the RCMP does not police in Ontario and they wear the red dress uniform for ceremony only, not for regular duty.

American Sheriff Bud Boomer pronounces "Toronto" like a native of the city (tuh-RON-oh), as opposed to most non-natives (tuh-RON-toh). This is clearly an in-joke, as John Candy, was born and raised in Toronto.

Boomer, Roy Boy, and Kabral are shown having to camp out for a night traveling from Niagara Falls to Toronto, and drive along rural roads to get there. While the two cities are connected by freeways traveling through densely-populated areas, and can be driven in a couple hours, many back road routes can also be taken. Bud and his friends are clearly incompetent and more than likely made several wrong turns along the way.

During the "Ballad of the Green Berets" sequence, the old lady in the black coat gets a gun before the guy in the big white jacket. When they are "marching," the lady is behind him. As this is a montage, there's clearly a time jump of several minutes or longer between the two shots, certainly long enough for their marching order to rearrange.

When they begin the hate campaign against Canada, they show someone sharpening skates like you would a knife or other edged tool. Skates are sharpened by squaring the blade (more or less...there's a slight concavity to perfectly sharpened skates) so that it puts extreme pressure on the ice as opposed to cutting it, with a sharp edge on either side for control.

Although the motorcycle cop makes a big deal of the bilingual signage policy in Canada, virtually every Canadian sign made for the film is in English only.

The United States of America flag patches on the right sleeves of the Omega Force members is not worn correctly. When worn on the right sleeve, it is considered proper to reverse the design so that the union (field of stars) is at the observer's right, to suggest that the flag is flying in the breeze as the wearer moves forward.

During the opening scenes, the camera vehicle is reflected the President's black Town Car limousine.

The motorcade at the beginning, which is supposed to be in Niagara Falls, passes Dofasco Steel, on Ottawa Street in Hamilton, Ontario. The factory shot from across the water is Stelco Steel, Dofasco's neighbor.

When Bud and his friends stop to look at the skyline of Toronto, they are on Leslie Spit, a peninsula and park to the southeast of the city. Immediately after, they drive from the west through the Princes' Gates toward downtown. While Bud and his friends are incompetent, this is a circuitous route even for them. (Additionally, private vehicles are not allowed to drive through Leslie Spit, but artistic license is obviously at play here.)

At approx 14 mins. Although he gets to the podium and has the microphone in hand in a few seconds, The President doesn't begin his speech at the Hacker Plant until almost a minute later. Just long enough for Smiley and Hacker's dialogue to finish.