[gumby79]

Originally Posted by slowmover

Agreed that braking isn't emphasized. At 70-mph the typical travel trailer or such won't have operating brakes before the end of a full on emergency stop.

If they are not working by the time the brake lights come on your system needs truble shot . Or just plain shot and replaced.
If you have a pendulum type you must calibrate "level"(plumb)or it will not work correctly. It could even act as you describe.
Drum brakes are less efficient as feed rate/speed goes up , it takes more application pressure to get the same amounts of brake force/speed reduction due to off gassing the brake shoes. Off the cuff EG 10A application will bairly slow @70 were the same 10A will lock up the trailer @ 10mph
At 25mph I spun the axle in the u-bolts well before stoping from the truck brakes . My mistake I did not confurm the settings before the cross town trip, it had gotten turned to max(6axle rated). Trailer was 16k 2 axle 5er .
With the Tekonsha brake controller I had,it had a pendulum to up the power above bace as g-force went up. If I experienced a lock up at highway speed, the force of the trailer sliding would apply negative g-force to the pendulum reducing the power applied , not enough to unlock the bace setting is too high for the traction sliding rubber provides checkup on the pedal spin the wheels reapply, wile simultaneously reaching down to adjust the controller and stearing to control the load in the mirrors and whats going on out front that caused the brake application. Ive yet to hit something .