You may also notice the “mud” I painted on the treads. This is just a dry-brushing of brown paint, although sometimes I use real mud for added effect. I also apply this to vehicle wheels, like on the Stinger and Vamp pictured below. The Stinger also shows some real mud applied behind the wheel to imitate mud spatter. You can’t have a weathered vehicle with clean wheels, can you?
The Vamp pic above also shows another nice detail to add to vehicles, namely painting in cockpit details such as seats and console, etc. It’s just a little thing that can add to the realism of a particular vehicle.