I have an 2007.5, 6.7 Commins w/6 speed auto. I use it to mainly to pull my boat. I live in the NW and do mainly mixed driving. It has only 26K miles on it as its is not my primary vehical.
This is a towing machine. At times I almost forget I have 8,000 lbs. behind me. I know some 3/4 tons can tow that. My last truck was a gas 3/4 ton and was rated for that much.
It was working way to hard.
Gas milage is great and will get better with age. In mixed driving about 13. Get it on the Freeway about 20 mpg's @ 65 running on 35's.
It tows very well. Even my buddy who has both a a 5.9 and a 6.7 Cummins(07 and 10). Loves the 6.7. He pulls a 35' 5th wheel with it. Both trucks can do it but the 6.7 is better at it. He said his 5.9 in the summer would DE-fuel to keep the temp down on the EGT's. But that was pulling up a hill in 95* heat.
I perfer the seats to be a little softer. I wasnt a big fan of the layout of the controls. I bought this Dodge for the Cummins engine. Like any new engines and new truck you have to work out the bugs. So for the last 1.5 years I have not had any issues with it.
This next issue is a big one.
Dodge uses a press-in bearing for for the front knuckles on its truck. They cannot be serviced. They only last about 80k or there about before they need to be replaced. To replace them each one is about 500.00.
My buddy(mentioned above) has replaced both on his 07 and has 126k on it. Prior to replacing the second one. He installed a free-wheeling hub kit. He is getting another 2-3mpg's.