My first tow vehicle was a 1977 F-150. It was low tech as all get out. I wouldn't want to go back to that. Yes, it was fixable in a parking lot with a screw driver and sandpaper but.. It also needed to be fixed in the occasional parking lot. The modern, computerized trucks and SUVs are far more reliable. If they breakdown it's entirely possible that they will need very specific parts and at least an OBDII reader to fix, or being towed to a shop. But, the likelihood of a breakdown is less.