Other mistake: After the state troopers collide with Bob's pickup truck, both vehicles crash into a fire hydrant improbably located alongside a deserted country highway. (01:29:45)
Other mistake: When Doolittle is running his jeep up the muddy hill near the beginning, the landscape changes. The hill is a straight 40° angle, but in the close shots behind the wheel, it changes to a steep 80° which no vehicle could realistically terrain, except perhaps an army tank. And he stalls out several times and has to back up, which would not happen at the 80* steep. Then he miraculously makes it over the top.