You have a knowledge of the surrounding places of interest, like gas stations, malls, places you frequently used before the apocalypse.
You start with a map, can stay up for longer and know where to possibly find trucks, warehouses and garages. You are not too picky about food and get less morale penalty for things, like being dirty, wet, etc…
Truck driver’s bonuses should be restricted to things that are definitively to do with the profession itself. Being resistant to morale penalties from being dirty, wet, eating crap food etc deserve a separate trait, in my opinion (e.g. Gourmand).
I have ideas for balancing the truck driver: he’s 50% slower at learning about computers, killing female zombies and healthy dogs (maybe for the elderly too if they get added) give moral penalty, that would be capped, say, at 100. Also, not driving for a while would result in moral penalty too.