During the opening gambit, when the missile is fired at the "American Relief Organization" truck, it rolls onto its right side, and skids to a halt in the same orientation, but seconds later, when the gunmen arrive to examine the wreck, it is lying on its left side.
About 22 minutes into the film, the pitcher of beer that Parker is filling at the bar changes as she's walking back to her table. The layer of beer foam changes between scenes.
At the end of the movie, Spider fills up Parker's fuel tank. He then gets back in her truck, they talk for a minute, and then drive off without paying.
In the opening scenes they are fighting in the desert. All sand other than the trucks. The truck is flipped on its side, the back completely open ... and not a grain of sand in the truck. Then Parker dispatches all these terrorists (in the sand) but when she is standing afterwards her outfit looks like it is brand new and there's not even a speck of sand in her hair or on her clothes, or anyone's clothes.
Parker gets off the bus at the start of the film and it's pouring rain -- she holds a small jacket over her head as she runs all the way to the sheriff's office. When she arrives and takes down the jacket, she is completely dry. Then like 5 minutes later she is done at the sheriff's and he is driving her home and the roads are completely dry and there is no sign of rain.
Speaking of the stolen truck, Parker tells Mike that there's a machine gun in there. Parker is special forces and would know that an M4 is a rifle, not a machine gun. Only someone who doesn't know one weapon from another would say something like that.