Spector41
Because of the difference in density between coal and woodchips, and the fact that loading woodchips into a car immediately after it had contained coal would contaminate the woodchips, coal and woodchips would not be delivered in the same car in real life. But things are somewhat different in Trainz, and not all real world conditions are applied. So you might try to load woodchips into the coal cars.
As to diesel fuel, if there happen to be tank cars in the session when you downloaded the route, you could use those. Otherwise, check the built-in items with your game, and you should be able to find one or more tank cars that will work in your route to handle the diesel fuel. And if the coal cars won't load wood chips, you might try the same technique to find suitable built in cars. If you are not able to find one or the other, then you may have to take recourse to the Download station.
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