I had a brake controller installed in my TV before I went to pick up my new Rockwood 1940LTD. The controller is the Curt Tri-Flex 51140. I started with the suggested output of 2.0 and at 25 mph, I couldn't feel any sort of slow down when I pulled the manual switch. After turning it up a few times, I could finally start to feel them at about 6.0-7.0, but it felt nowhere near having the wheels lock up. Even at 9.0 I feel a good amount of tug, but still nowhere near enough to stop the TV. I feel like 9.0 is way too high. Am I even doing this right or could there be something wrong with my setup? Haven't been able to check the output with a multimeter yet.