I don't know what data they have that there are "increased braking loads". I'm sure they have none. Disc brakes don't stress any components. The only data ever documented is that disc's heat up less. Thus not as much fade. Other than that, the truck does not know what system is stopping it. There are good advantages to disc brakes. On dry flat roads, they really don't stop better.
I assume this vendor was making an attempt to be an armchair lawyer trying to dodge liability of some sort.
A Jr. Engineer that learned the word compressive loading. Did not accomplish anything except loss of credibility.
Never heard that front edge of tires "spread" during braking. I assume the "built in" refers to a component that is already "bent" from stopping with drums and would therefor be aggravated by adding disc brakes. All hogwash. Don't worry about any of that.
About 66% of stopping "load" is taken by front brakes due mostly to weight transfer and front end motor weight.
The relatively small size of tie rods, their diameter to length ratio, tells you that they do not see large "bending" loads from steering the truck, pot holes, bumps or braking.
We've heard the term "bent tie rod" in our lives. Those are from impact on a rock, log, curb, etc.
