As far as fuel additives you dont need to run any in any of the trucks, I always run diesel kleen though.
I believe he is referring to the DEF fluid since he mentioned about rams being the only ones on the market not using it (which rams can and chassis trucks already use a DEF system)
Esai brought up some good points to DEF fluid
Something other things to consider
DEF is a water ammonia mixture so it is renewable unlike diesel
11-12 powerstokes are averaging about 15.5 mpg vs 11-12 cummins 14.1 mpg
Over a 7,000 mile interval (about how long 6-8 gallons of DEF fluid will last) the powerstorke uses 44.8 gallons of diesel (at $4.11 a gallon average in the US) less then the cummins
So by useing $32 of def fluid (2.5 gallons is $10) the powerstroke saves about $150 in just 7,000 miles (over $4,000 over 200k miles)
And somebody might live an extra day because we polluted less are some hippy crap like that
By no means am I saying powerstrokes are better and these aren't exactly the best conditions to compare but even at 20% error it's still saving over $100 over 7,000 miles
But you do have to get the fluid and fill the tank which is such a foreign idea for so many people...