another try at posting!!
nothing is really changed, a local well respected rv dealer and his mechanic suspects the brakes are simply too small, dexter agrees
fully serviced, lubed, new wiring and I can pull the trailer almost normally with the breakaway pulled out. with the trailer jacked up, I cant turn the wheels with the breakaway pulled
I even went for a drive (100 km or so) actuating the brakes manually lots, still very little braking action with the controller set at 100% output
so my next step is get a used 10 inch backing plate and drum from the dealer and see what the difference is. I suspect bearing id but the spindles "look" the same as our previous tt with 10 inch brakes. if I can, i'll mount the used 10 inch and try it