Most all travel trailer use electric brakes. Some are self adjusting, some are not. You can jack up your TT and check your brake adjustment and see if they are dragging.
What kind of brake controller do you have? Is it an aftermarket add on? Is it possibly not a progressive type? My first one was a timed type, the longer you activated the brakes, the more current supplied for more pressure, locking up and overheating the brakes in hilly areas. I had mine smoking and smelling BAD! Wheels hot to the touch.
Last have your transmission and transmission cooling checked out. I think if it overheats you will lose power.
