From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Cross-section diagram and gear ratio table for a new Maybach transmission for large vehicles.
| Identifier | ExFiles\Box 22\5\ Scan034 | |
| Date | 2nd March 1931 guessed | |
| Engine end #1245 Section Through New Maybach Transmission for Large Motor Cars, Buses and Utility Vehicles Speed | Reduction | Over gears IV | 1:1 | Direct III | 1:1.5 | 1-2-4-3 II | 1:2 | 3-4-5-6 I | 1:3 | 1-2-5-6 Ia | 1:4.5 | 1-2-7-8 Reverse | 1:4.5 | 1-2-7-9-10-8 | ||