Shop Aftermarket Drum Brake Parts for the Mack CV/GU. Our comprehensive inventory of drum brake parts for the Mack CV/GU can keep your medium-duty work truck functional for years to come. Select from brake drums and shoes to essential hardware; we ve got what you need for reliable performance. Upgrade or maintain your brakes with durable components built for extended lifespan and road safety. Find the perfect fit for your Mack and get back on the road with confidence!