How is vehicle towing capability validated?

Towing validation tests include: Grade climbing at maximum trailer weight (sustained and launch), cooling system performance (thermal soak, hot shutoff protection), brake performance and fade with trailer, stability under various conditions (crosswind, lane change, emergency braking), powertrain durability at sustained high loads, and transmission shift quality with load. Testing covers altitude, temperature extremes, and various trailer configurations. Results establish maximum trailer weight ratings and towing speed limits. Trailer sway mitigation systems require specific validation.