If you have full time 4wd wouldn't all 4 wheels have braking applied whether you used front or the rear brakes. As long as the transmission is in gear? Not taking into acount the front diff.

 

Yes, all 4 wheels will brake. If only one front wheel has traction, more braking effectiveness may or may not be obtained by using the brakes seperately, but for the most part the front and rear axles are locked together when you have full time 4wd.