Trailer brakes sucks

If it's like drum brakes on other vehicles, there's a "short" and a "long" shoe on each brake and the "short" also called "primary" has to be on the forward side of the brake. Short shoe to your right on curb side, to your left on driver side. At least with hydraulic brakes...

I just went through this last year with my Al-Ko brakes (4400lbs mind you). it turns out my old controller was feeding a small amount of power to the magnets and they were dragging.

Eventually, after a lot of replaced parts (complete back assemblies), the drums were worn down to the stud!

Check your drums. I found them worn down. if they are worn down, you're looking at between 125-150 per drum to replace them.

If you're like me, you can order new axles, drop shipped near you, and install them faster than doing the drums and backing plates...

just my two cents...

josh

What boost level are you at? Try turning it up. I am at 3 out of 5 and think I might try 4.

Did you turn the drums? Shoes will wear in so much better if you do.
Have you rechecked the adjustment?

Shoes. Fixed it.

Lock up sitting still? Display says 10. At full power it will stop if rolling backwards on an incline

Tow vehicle is 03 dodge ram2500 diesel. Proportional controller. Worked well for my other toy hauler but that was much lighter. At full power I expect it to feel like a normal stop of truck. If I hammer on the brake it seems to stop alright. But no gear yet, another 5000 pounds will be added.

What's your TV? Integrated braking? What are you expecting? Integrated braking is much smoother than the old brake controllers.

The only electric brakes I know have shoes.
Something new on the market?
Bare in mind new brakes need to break-in and bed-in.
Doing the bearings, you did not get grease on brakes, did you?

Will they lock up sitting still?