Just as a follow-up to all who responded, we returned yesterday from our 800mile trip to northern Wisconsin with the Terry 31' TT and our 2008 Chevy 2500HD w/6.6L Duramax diesel. The trip was great and I loved how the TV responded in every way. I really do have a big smile on my face and am very happy with the TV. We averaged 12.5mpg on the way up and 11.9mpg on the return trip with plenty of pulling power to spare. Based on my previous experience with our 1/2ton Chevy 5.3L gas TV, the difference is like night and day. With the old TV we averaged around 9.0mpg, which even at $3.00 fuel v $2.80gas, amounts to almost a 20% improvement in cost per mile! The power in the new vehicle is the most impressive, pulled our TT like it wasn't even there. I didn't scale the loaded TT, but am guessing it to be around 6,500lbs (4,350lbs dry wgt + gear, fuel, passengers, etc.). To anyone considering purchasing this TV, I would highly recommend the Duramax and would rather have excess towing capacity than the other way around. It not only feels much safer, it is much safer!