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).
Oil specifications for engine, transmission, and rear axle for summer and winter use.
| Identifier | ExFiles\Box 127\2\ scan0028 | |
| Date | 22th September 1933 guessed | |
| - 3 - Oil Specifications: Engine. Winter-in range of S.A.E. No.30. Summer-in range of S.A.E. No.40. Transmission and Rear Axle. Winter-S.A.E. 90 F.W. Summer-S.A.E. 110 F.W. | ||