Great truck for the ride & comfort. The 6.6 Diesel has exhaust re-gen problems, GM says there is no fix, get used to the smell of exhaust in the cab. I would not recommend the $8,000 for the diesel, go with the 6.0 gas engine. I get 7-8 MPG pulling a 34' 5th wheel...lots of power, lots of exhaust fumes to contend with. The Allison trans is a great feature!
The Allison trans with 360 hp in front of it. Can pass everything on the road except a gas station.
Work on the exhaust problems. Then they'll have the best truck on the road. Rear air would be nice for the rear passengers.