Most cars are front wheel drive since it's a tad easier to control and saves cabin space and weight.
When I attempted my own top down Box2D car last time, I left the body with no damping, no linear friction, and no angular damping..
I also think I was testing around with giving the wheels no friction, some linear damping, and small amount of angular damping.
It would probably be realistic to use friction for terrain differences, if you can somehow make it so the whole car passes through larger objects that represent different ground materials.. I haven't thought about how that might work though.
If I have time I'll look for the project file, but I don't think I got it to very satisfying level anyways. I started working on something else.