In the wrecker yard when the helicopter finds JD, he runs forward and jumps over the hood of a green car. However just moments before you can see this car was 20-30 feet behind him. The gold Pontiac LeMans is a good point of reference too in both shots.
The helicopter used changes colors from red and white to all red to all yellow at different times even though it is supposed to be the same helicopter.
Strode and JD are about to fight, Strode smashes a bottle against a fence with just the bottleneck left in his hand. Next moment, there is a long shard of glass with the broken bottle.
Despite driving through clouds of dust and dirt while eluding the police, Dawes' van is spotless and clean when he drives up to Arlene's house.
The same Plymouth Valiant and Lincoln are smashed twice in the compressor machine in the junkyard.
When Dawes is running into the wrecking yard, the helicopter pilot yells "Dawes is in the yard!"... but the closed captions show "Strode is in the yard!".
Chuck Norris's character is shot in the stomach with a revolver at close range leaving him limping with a visible bloody wound. This wound completely disappears when Norris fights Don Gentry despite at most a few hours passing between the two scenes.