My impression is that GM had trouble making the Voltec drive train work in larger cars. The Volt is a low-slung, very aerodynamic car. As soon as you turn that into a crossover (as they were rumored to be doing) or a small SUV, both range and gas mileage are going to suffer.

It's too bad. We have a Volt and I would have loved the same drivetrain in a car with more ground clearance and a bit more cargo space.