Up until around 94 the only axles that have an emergency brake r the drives. 2 good opperating chambers r safe. If u loose preformance on 1 of the 2 Id be real careful about setting the emergency brakes and walking away with a toad hooked on ANY SLOPE. It might hold it, it might not. If the 1 remaining hub lets say has some oiled up pads from a leaky seal u will be off to the races. Be carful take no chances with chassis that only have emergency brakes on the drives.