1238. I think the vehicle system designers are leaving some things on the table when it comes to differing sounds for cars with their engines, mufflers, or suspensions in a low condition state. Take for example this messed up MFP pursuit vehicle:
This would be a great audible cue to let the player know why his / her vehicle is attracting so many zombies.
Also, I'd love to see squealing, smoking tires from cars and trucks with high enough horsepower.