RAS43 wrote:
I do not believe that drum brakes have much stopping action in reverse do to the design. And as mentioned, traveling a few feet wouldn't engage them much.Disc brakes could be stronger.
That may have been the case back in the 1960s and you have a dirt cheap inertial controller but drum brakes from the ones I have used from the 1980s up certainly work equally well in reverse.
If OP has not recently checked and adjusted their drum brakes a good chance that they need adjusted. They do wear down and/or wear out and most are not "self adjusting" so in reality one should physically pull each drum, adjust/inspect once a yr (12 months) or every 12,000 miles whichever comes first per most axle manufacturers recommendations.
Very few RV'rs ever bother with this maintenance.