When Thelma is on the car about to be raped Louise comes up from behind with the handgun. Just before you see her put the gun to the guys neck we hear the gun being cocked. When we see the gun placed to his neck it is not cocked.
The boom can be seen in the reflection of the car bonnet when Thelma, Louise and JD stop the car after taking a diversion on the dirt path through the industrial yard when they see police ahead of them coming in their direction.
Towards the end of the film, where Thelma rings Hal Slocumb the state police investigator, the FBI are in the same room as Hal, recording the telephone. Watch for the guy at the tape recorder - he's messed up his headphones so much that the left ear cup is pointing out rather than pointing in. Professionals do often listen with just one cup (to retain some ambient sense), but never like this.
In the wide shot of the state police cruiser, in whose trunk Thelma and Louise have locked a state trooper, just before the Rastafarian cyclist approaches the car it is just in the shadow of the mountain on the left. In the close-up shots of the cyclist approaching the car, the car is completely in sunlight.
When Darryl is being talked to by the police about having his phone bugged, it's clearly supposed to be raining, but in other shots, while you can still hear the rain it's bright and sunny in the background.
When Louise is laying out her plan to go to Mexico, the cut on Thelma's lip from hours before is gone. When she bumps into J.D., he comments about it and then Thelma sits in the car and the cut is there again.
In the scene where Thelma meets Jimmy at the motel to get the money, it is very obviously nighttime as seen through the windows. However, moments before entering the motel, it is daylight. It is daylight (but clearly a little later) again when they are back outside.
The camera on the crew vehicle can be seen in the reflection at the rear of the car on the chrome trim when the T Bird passes. This is just after Louise talks about getting away from their last crime scene.
The scene where J.D. first asks Thelma and Louise for a ride is supposed to take place in Oklahoma; the newspaper Louise buys is the "Daily Oklahoman". However, a freeway entrance with a green triangular California state highway shield can be seen clearly in the background.
When Thelma and Louise enter a diner to phone Thelma's husband, Thelma uses the pay phone correctly by dialing the number first and then inserting coins. Right after she hangs up, Louise uses the phone but inserts coins without having dialed first. In real life the coins would have come back, as a number has to be dialed in order to know how much to put into the phone.
Bullet holes fired at an angle into sheet metal will leave elliptical holes, not circular ones. Additionally, they will cause the metal to bulge away from the gun that fired the bullet, not towards it.
Thelma and Louise leave for their trip on Friday night, the next day after the shooting they are in the car trying to figure out what to do, in the background you can hear the AM radio giving the Dow Jones Industrial averages like the stock market is open. This would not happen on a Saturday.
After the girls lock the state trooper in the trunk of his cruiser, they throw the keys into the desert toward the right of the car. Later, the trooper, still locked inside the trunk, points through a bullet hole with his finger, indicating to a passer-by where the keys were thrown. Despite assertions that he could not know where they were, it is not difficult to judge direction or even distance just by sound, especially a sound as distinct as keys hitting the ground.
During the big chase scene, the Thunderbird Louise is driving hits a police cruiser and knocks off a side mirror. However, after the chase scene, we can clearly see that the mirror is still intact and on the car. This is because the mirror that we saw fly clear was from the police cruiser, not Louise's Thunderbird.
In the Thunderbirds of that era, when the top was down there was very little room to put anything in the trunk as the top took up most of this area. When they are putting the luggage and fishing gear in the trunk, with the top down there would be no room for all the luggage and the top in the trunk. The most that could have gone in the trunk would be two small overnight cases and no room for the fishing pole etc.
When Hal looks up Thunderbird owners in the Arkansas State Police database, each owner's name is listed in alphabetical order. The corresponding list of vehicle's year / color is listed in chronological order, a coincidence unlikely to happen in real life.
After Thelma and Louise blow up the rude trucker's tanker, they drive their car in rings around him. But the trucker is already standing in the middle of a ring of darker-colored freshly turned earth left by a previous take.