What fuel economy do you get on that duramax? City? Highway? Where I live in Canada, there's a huge price difference to go from the 6.0L gas to the 6.6L Duramax diesel. I was quoted $44K on the road for an ext. cab SLE with the 6.0L gas and $55K for the diesel version. An $11K premium is a lot. You have to wonder if the fuel savings will offset the initial extra cost and the higher maintenance costs on the diesel.