Can someone clarify how the 4 wheel drive should work on my 2008 Sorento. It has the knob that you select 2 wheel, 4 hi, 4 lo. Last winter we noticed that on snow and ice, if you hit the gas pedal, the rear wheels spun and the front wheels did nothing in 4 wheel mode. My dealer told me this is normal until it senses rear wheel spin and then shifts power to the front wheels. I was under the impression with this type of 4 wheel drive, once you put it in 4 wheel mode, it should work right away, not after sensing rear wheel spin.