if there stuck on dojj jack the wheel up and spin it by hand you'll soon see if it's binding, or jack the front up start the car leave it in 2nd or summit press the brakes slightly till it nearly dies let the brakes off and see if the brakes are still binding on one of the disks, it'll just have the one wheel spinning hopefully as the diff kicks in.

or stop being a lazy bastard and take the calipers off and give them an inspection and a clean