I've been working on a few mods recently using mostly developer models, and I've noticed that models are smooth but I don't believe the subsurf modifier is used as things like tubes still have 8 sides unlike multiplied amounts of sides like the subsurf modifier does. What do they use to smooth the models without adding vertices?
Right click you model and select shade smooth. The devs also use edge split on most parts since shade smooth can cause some weird shading issues, especially on exterior parts. Edge split is usually set to 30, but you can make it higher for smoother edges. Using lower poly models by doing these things is very important for beamng since high poly models cause spiky deformation. Another benefit is better frame rates but the first reason as much more important.
