Not even close to the record! This was posted last year by TDR forum member Guillorytransport ...
"Just thought I'd post that my 2012 has 612k miles on it. Just replaced original 68RFE transmission with a mopar reman today. I hall cars (25k lbs combined) all day everyday for last 3 years. The truck has been awesome. No one believes I have original engine, turbo, etc. I'd hoped to get more out of transmission, but I'm told 600k is 3 times longer than it should last so $4000 installed is not bad I reckon. Of course it's had bearings, seals, ball joints, ujoints, and all of that a few times and the typical batteries, alternators, water pumps etc..., but it still surprises people that the engine and transmission have held up. Curious what y'alls experience has been. 3.73 gears and 4WD towing about 15k daily. Truck has auxiliary fuel, flat work bed with tool boxes, airbags so it weighs about 10k fully fueled.
All of the interior and electrical has held up well. Not your grand dads dodge. Anyway, your thoughts