Here's the screengrabs I promised. Cooter's first tow truck was this brown 1969 Chevy. This picture is from 'Repo Men', but the truck first appeared in 'One Armed Bandits' (see inset) without the plank of wood. I don't think it was driven by Cooter in that episode. The blue and white 1967 Ford gets used from around the middle of season 1. This picture is from 'Money to Burn'. The inset is the same truck as the impound truck from 'The Big Heist' a couple of episodes earlier. For season 3 and the first half of season 4 Cooter drives this yellow late '70s Ford. It appears many times, this picture is from 'Good Neighbors, Duke'. In the second half of season 4, Cooter reverts to blue and white trucks. The '67 Ford reappears in a couple of episodes, eg. 'Goodbye General Lee'. The Chevy below makes a few brief appearances, sometimes swapping places with the Ford mid-chase - this picture is from 'Cletus Fall in Love' where Cooter's truck is a Ford as it leaves town, a Chevy during the chase, a Ford as the chase concludes, and a Chevy as everyone gets out!. You can easily tell the difference; from the front the Ford has a very white grille, and from the rear the Chevy wrecker bed extends over the rear wheels.