When Michael does the weapons 'sale' with Khan the back hatch to his vehicle's tray switches from open in the first shot to closed, at which point Michael then opens it again.
During the truck setup montage, Michael says that a strut across the engine lowers the center of gravity of the truck; actually it is to stiffen the chassis and prevent the shock towers from collapsing inwards due to the impact of the shocks over rough terrain. The montage also never shows the strut, but shows the shocks when the strut is mentioned.
When Michael tells Sam to pull the chain off the bike, and Sam kicks it off. Bike chains are incredibly difficult to break, by design, so kicking it would have done nothing more than maybe taking it out of gear.
During the high-speed chase, Michael tells Khan's crew to "turn left at the next block," which Khan repeats in Chinese to the driver, but he says "turn right in two blocks"which is translated incorrectly.