Yes and no. You cannot define the rear wheels for steering, but you can use the XWheels add-on to add an additional steerable axis, that you move behind the original rear axis. So you get a 6-wheeler with two steerables axes, the non-steerable axis in the middle. You can then move the original front axis close to the center axis. This axis is not used and invisible in the rendering if you don't put geometry objects in the wheels.
This workaround works very well with quite slow driving vehicles like forklifts or diggers.