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).
Synchromesh inefficiency due to heat and suggesting a gearbox oil change.
| Identifier | ExFiles\Box 97\4\ scan0074 | |
| Date | 26th October 1938 | |
| To Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} Chateauroux. 4006 Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}4/MH.{M. Huckerby}26.10.38. We have been trying to think of reasons why the synchromesh becomes less efficient as the box gets hotter. A simple suggestion is that it is due to the reduced viscosity of the oil. Will you please therefore, change the oil in your gearbox to SAE.50 and let us know whether there is any improvement. If you have no Price's "CW" at Chateauroux, Vacuum "BB" or Shell "Triple" or "Golden" are probably obtainable at a local garage. You have not sent us figures for the maximum temperature reached by either the gearbox or the axle, and these we should like to have. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||