its all BS, its not going to matter which tune you are in.
i have towed more stuff than most anyone on here and rps and i have had the tuner with bama's tunes on it since 15k miles on the clock. i have had it in both and have been running 87 performance for the last 30k miles and have done alot of towing.
perfect example is i ran 80-85mph with OD on and off for 5 hours to the dunes pulling 3500+ lbs while being on 35" tires and not to mention i had 83k miles on my truck at that point.
its not going to matter which tune you are in.
that guy that blew his engine just had a stroke of bad luck. also he towed through mountains and we have no idea what his maintenance routine was.
towing is always harder on your ride, you have to plan your maintenance around how you use the truck, whether its for towing, mudding, wheeling, or for a DD.
2003 Ford Ranger Lincoln Powered 5.4L DOHC, 42s, COs, D60s, 203/205, 4points, caged, full hydro, 3link front and 4 link rear.
1998 f150 bone stock baby hauler...