Automatic Transmission Rebuilders Association - ATRA is an international trade association for automatic transmission repair professionals. Automatic Transmission Service Group - ATSG is the largest, Employee-Owned, technical support service in the Automatic Transmission Industry. FindATrans.com - Consumer guide to transmission repair information. Local transmission shop and price search engine. ID a torque converter - Help with identification of a torque converter. A Short Course on Automatic Transmissions - Long article explaining the concepts behind modern automatic transmissions and their repair. Transmission Rebuilders Network International - World-class transmission rebuilders from around the world interacting on transmission diagnostics and repair.