tow vehicle tires and trailer sway

Never heard of that one.  I have had new tires on my 94 F-150 and never experienced sway pulling our 177.  On the other hand we could never travel above 35 mph with our 08 Explorer and NOT have sway.  A sway bar was mandatory on that vehicle.  With our 13 Explorer we have traveled at speeds of 55 mph w/o sway bar and again, no sway noticed.  I did that for a test even in cross winds, otherwise I use the sway bar link.  The only reason i can figure on the difference of the 2 Explorers was the width between the tires.  The newer one was wider, hence better tracking.  As far as pulling with our '95 F 150 with manual transmission my only concern is hitting more deer.  With 320,000 miles it has 31 deer kills, good thing it sits tall and has a real bumper on the front.  Have already hit 3 so far this year, but no kills as far as I know; even though they were pretty well banged up.  Would not want to hit one with the Explorer, with one hit I think it would destroy the vehicle.  Tires on all 3 vehicles above were the standard size that came on them when purchased.

First I have heard this one too. I can say my D rates handle better than my 14" C rates. As far as sway not noticeable. I eliminated my sway issues very early in my Pod towing experience.

When radial tires were new o the American market I worked in a gas station and we were told to tell customers that the first 100 miles the tires were breaking in and traction issues could occur.  They also could not be rotated so they moved in the other direction than they had originally be mounted.  My tire dealer tells me this is no longer the case on either.  My bet this internet wisdom is old.  I cant imagine the liability a tire manufacturer would have if they sold tires that caused sway.

Jato, by chance do you have a crash bar on the front of your F150 and enjoy road kill tenderloin?