More sounds for tire slipping should be added, based on wheelspeed vs airspeed. For example, when airspeed is 0, and wheelspeed is 10kph, the squealing of the tire shouldn't be there, or at least be as intense as it would be at a higher wheelspeed/airspeed ratio. In slow wheelspeeds/low-grip situations, it should me more of a scuffing sound. I believe forza does this, and in Beam.NG it would be really good for realism. Lots of examples -
Wheel squeeling doesn't depend on relative speed difference between air and tire. But rather more on how the tire is made and how the air is trapped between the tire and the ground.
To get a good idea of that... if you have a car with either a tight turning radius, wide tires, or a lot of weight you can try this little experiment for yourself. Go into a parking lot that has nice, flat, dry pavement. Take your car with one of the 3 requirements above, cut the wheel all the way to the left or right (doesn't matter) and proceed to drive around in a circle with the windows open. Now when I say drive, I don't mean at any high speed, I just mean merely driving around in that circle. In this process you should get some parts of the rubber on the tires to be traveling at different speeds than others. This should actually be enough to produce a small squeal from the tires. Enough to be fairly audible actually. I know this is a thing because I have to turn my car around in our parking lot at work every day and it does this every day. The one thing I have going for me that makes this happen is my car has very wide tires so the inside and outside of the tire will be traveling over the ground at a large enough difference in speed that it actually creates slip. Just that little bit is enough to get the tires squealing.
