The rear wheel bearings on the swing axle suspensions are set up like pinion bearings in a differential.
This means they are squeezed until a crush washer between the inner races is crushed such that the bearings are tight (NO endplay) and it takes a prescribed force to turn the assembly. The force on differentials is about 10-20 inch pounds.
This force (10-20 inlbs) is that which it takes to spin the flange. This force is due to the bearings running tight. Loose bearings such as properly tightened front wheel bearings would have no such force to spin the front flange.
I am guessing that you haven't started to get it tight. Feel the flange. Can you feel endplay. If so you are still way too loose. Over the years I have stripped out a half dozen new nuts trying to get them tight enough. I now start by dimpling the crush washer with a hammer to cause a stress riser that facilitates its crushability.
Bosch Master, ASE Master, L1
33 years MB technician