Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5060156 | Method and apparatus for determining engine oil change intervals according to actual engine use | Jeffery L. Vajgart, Peter W. Misangyi, Parshuram G. Date, Noel A. Walker, David A. McNamara +1 more | 1991-10-22 |