The all new GMC Yukon grows six inches and gains a new independent rear suspension. That means 66% more cargo space and 40% more room in the 3rd row. A choice of two V8s and an inline-6 diesel too. Tom Voelk checks out the all new rugged AT4 model to see if GM has raised the bar high enough to compete (or beat) Ford Expedition. Sorry folks, would have loved to taken it off road but with only one day with the Yukon, the location was closed.