The John Deere AL36391 is a genuine OEM alternator regulator designed for optimal performance in a wide range of John Deere agricultural tractors. This essential component ensures stable voltage output from the alternator, protecting the electrical system and extending battery life. Engineered to meet John Deere's rigorous specifications, it provides reliable power management for models including 2040, 2140, 2250, 2450, 2650, 2850, 3040, 3140, 3050, 3350, 3650, 4040, 4240, 4440, 4640, 4840, 8430, 8630, 8440, 8640, 8450, 8650, and 8850.