On a long hill, one that tend to cause acceleration while off the throttle, it is better to set you gearing at the top of the hill and descend the hill in the same gear you climbed the hill in. Tapping the brakes frequently while going down that type of descent you are running the risk of overheating them and losing them at which point it is time to look for the run off ramp.
if you did not set the trans at the top of the hill and your TV has tow haul mode, and you are using it, it should downshift and set the trans the first time you tap the brakes.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles