Okay guys I'm going to start addressing the suggestions people have made with potential solutions. Feel free to respond back.
As for the trucks, yes they look very empty in the middle (as Simon said) but it is because:
1. Detailing the actual motor components would be large in number of polys decreasing the performance drastically. Here is a picture of the middle of the truck.
Another reason is because I am not expert in modelling that type of complexity. ;-)
2. In real life you can't see those components anyways. Why? Because it's hidden in the shadows. Look at any real pictures of the R46 facing directly towards the front end and you can see the middle the truck is pitchblack.
Most modern train simulators with high-end graphics have real-time dynamic lighting which creates a realistic shadow effect.
Here's an example:
As you can see the middle of the trucks are darkened and you can barely make out what's there. Even the tracks are blended with the shadow from the train. Unfortunately I don't think Openbve does this which makes the trucks look unrealistic.
This is a sacrifice I made for making 3D trucks in Openbve.
I attached a screenshot to clear up any misinterpretations from the video.