Revealing mistake: When Frog makes her "We're going 110." comment, they then show a close-up of the dash-board. Even though the speedometer does show them to be going 110 (albeit km/hr, not miles), the ignition key is in the 'off' position, and the 'amp' gauge shows '0'. This is a clear indication that the engine was not actually running during this shot.
Continuity mistake: In the scenes where Sally Fields is removing her wedding dress and veil and throws them out of the car you watch the veil leave the car and fly away, in the very next scene the veil is back inside the car as she struggles to get it to fly out of the car again, as it is caught on the t-top.
Continuity mistake: While at the truck stop to refuel, the Bandit talks to Justice on the CB. During this scene, Justice is having his car worked on the front is up on a jack. When the bandit drives by them to leave, you can see Junior is wide awake (in fact, his head turns to look at the car) and then immediately in the next shot he is sleeping.
Continuity mistake: When Sheriff Justice tries to drive off while on top of the jack (at the gas station), his car falls off the jack, as he hits the red car in front of him, in the car's rear quarter, spinning it around. In the next shot of Buford, the red car is back to its original position, with Buford's car on top of the red car's roof.