I’m at 6,000 miles now with about 2,000 of that towing a 26’ camper through the Rockies and another 1,500 towing a boat. No problems in any of the towing and the downhill grade shifting/engine braking of the 6L90 is very nice. Fuel economy isn’t great, about 1-1.2 mpg less than the Duramax. Towing at 75mph with a wind catching camper is around 8’ish. Dropping to 65 mph gets it up to around 10. Empty is 14-15 or so. The best was a highway trip at 60-65 mph for 18.5 mpg. All of this is around what I was getting with my 2011 LML. Of course, gas is typically less than diesel. The power is there, no problems going over Colorado passes at 12,000 feet with the trailer. So far I am happy with the switch. There is a clunk coming from one side of the rear suspension when off road. I am sure the dealer will fix it. Other than the clunk I have zero complaints, and the 6.6 gas can really scoot when needed.
