Collection: Auto - Manual Case

Restore the structural integrity and smooth gear reduction of your gearbox with our selection of Auto Manual Casecomponents. At DIY Customs, we provide high-strength replacement manual transmission cases, durable cluster gears and counter gears, specialized countershaft bearings and races, and heavy-duty case gaskets designed for a perfect fit. Whether you are repairing a cracked transmission housing, replacing a worn cluster gear with pitted teeth, or performing a comprehensive countershaft overhaul on a classic gearbox, our professional-grade hardware offers the mechanical strength and precision alignment you need at unbeatable prices. From specialized case plugs and thrust washers to complete countershaft assembly kits for popular manual transmissions, we carry the essential gear for every internal rebuild. Don't see the specific gear tooth count, case casting number, or specialized countershaft part for your transmission? Hit the live chat or call 412-882-8346—we can special order and drop-ship exactly what you are looking for directly to your doorstep!