The Grand Cherokee keeps on changing from the older body style to the newer.
The SUV's odometer reading does not change
When you see 405 Freeway for the first time (21 second of the movie) one of it's strips (left) is occupied by cars and second one (right) is empty (with only main character cars on it) - prepared for emergency landing of a place on it. When you see it for the second time (00:34 of movie) in the scene where an airplane is approaching to the ground, both strips are empty of cars.
In 73 second (01:13) of the movie airplane hits the car and immediately nose gear closes, so the first part of plane lies on the car. Impact of landing gears to the ground is so high that all the gears are heavily locked by a special locking system and it is simply impossible to close the nose gear by only hitting a relatively small object like a car.
In 73 second (01:13) of the movie airplane with own nose gear closed lies down on the vehicle. Weight of landing plane is 100 - 400 tonnes (according to the amount of fuel left). With this weight car would be simply smashed to the ground and destroyed.