I have a 2008 Jeep Grand Cherokee Overland with the Mercedes diesel. Jeep uses a 5 speed transmission, so the mileage is about 23 highway (not towing) and 17 highway (towing a 1963
It has plenty of power. No downshifting. I can barely feel the difference when I am towing.
I bought this vehicle because I wanted a modern car with the "classic" look of a 70's Jeep Wagoneer used in airstream ads. My Dad pulled a 1962
Overlander with a Wagoneer. We put thousands of miles towing all over the United States, Canada, and Mexico. I never remember having any problems.
Having owned several Mercedes vehicles (2 diesels) I know this engine is probably good for the rest of my towing life (I am 59).
WBBCI #1200 (my Dad's original number acquired in 1956)