TM 9-2320-209-20-3-1 12-4. REAR AXLE BREATHER VALVE REMOVAL AND REPLACEMENT. NOTE This task is the same for both forward-rear axle and rear–rear axle breather valves. TOOLS: 7/16-inch wrench SUPPLIES: Solvent, dry cleaning, type II (SD-2), Fed. Spec P-D 680 PERSONNEL: One EQUIPMENT CONDITION: Truck parked, engine off, handbrake set. a. Removal. FRAME 1 1. Using wrench, unscrew and take out air breather valve (1) from axle housing (2). END OF TASK 12-4