The AOD transmission is a four-speed automatic overdrive unit developed by Ford to improve highway efficiency without sacrificing performance. Commonly found in rear-wheel-drive Ford, Lincoln, and Mercury vehicles, it features an overdrive gear that lowers engine RPM at cruising speeds. This helps reduce fuel consumption, engine noise, and overall wear. Its hydraulically controlled design makes it simpler to service compared to newer electronically controlled transmissions, making it popular for classic car restorations and daily drivers alike.
