FEL lifting capacity

[carpenter383]

This does not make sense to me. If I have all four tires off the ground using the fel and the backhoe outriggers, and with the brake pedal depressed, and in 4WD, I can turn the front wheels both forward and backward but cannot move the rear wheels. Engine braking though does hold back the tractor from gaining speed going down a hill with both front and rear wheels.
There is obviously something here that I don't understand.

Were you just turning one front wheel? The front axle has a differential that may make it SEEM like the rear brakes don't affect the front wheels in 4x4. Next time try to turn both of them in one direction and I bet they don't move. If you try this again look at the front driveshaft while spinning the front wheels it won't be moving if you're in 4x4 with the brakes on. This is because of the spider gears in the differential. One wheel will turn opposite of the other.