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).
Changes to the viscosity and naming conventions of Wakefield Oils.
| Identifier | ExFiles\Box 145\2\ scan0176 | |
| Date | 16th February 1938 | |
| 1231 By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} c. Hs.{Lord Ernest Hives - Chair} Rm{William Robotham - Chief Engineer}/Gry{Shadwell Grylls}2/R.16.2.38. WAKEFIELD OILS. Mr. Limb, to-day, gave us advance information that from April 1st they are changing the viscosity of all their oils. XL, which was S.A.E.50 is becoming S.A.E.30, the only thinner oil will be known as 'Castrolite' S.A.E.20. XXL will come down in viscosity to S.A.E.50. We told Limb, as we have done several times before, that the XL recommended in all Rolls-Royce Instruction Books up to date will no longer be suitable for those engines. He said he realised this, but as the name'XL' was a great selling feature, and no manufacturer wanted an oil thicker than S.A.E.30, it had become necessary to call their S.A.E.30 oil 'XL'. We also told him that, in all probability, our Instruction Books in the future would merely tell customers to use a certain viscosity oil made by one of the reputable oil companies, and that the reason we were doing this was because of the trouble trade names caused. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||