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).
The mileages and failures of rear axle shaft bearings for various chassis.
| Identifier | ExFiles\Box 114\1\ scan0365 | |
| Date | 15th February 1944 | |
| COPY. To Wym.{G. Harold Whyman - Experimental Manager} from Wym{G. Harold Whyman - Experimental Manager}/C.Lee. c. to Rm.{William Robotham - Chief Engineer} Wym{G. Harold Whyman - Experimental Manager}/C.Lee.5/OH.15.2.44. We give herewith mileages and failures of Rear Axle Shaft Bearings to date. CHASSIS. 30.G.VII. The off side axle shaft ball race Hoffman 345 failed at a total of 66,994 miles. This was a standard ball race, and the holes in the ball cage had not been elongated before fitment. A new ball race, Hoffman 345 was fitted and the holes in the ball cage elongated .100". This ball race failed at a total of 41,237 miles. A similar ball race was fitted again to the off side shaft and the holes on the ball cage were elongated .050" to FJH{Fred J. Hardy - Chief Dev. Engineer}'s instructions. The above ball race has now failed after a total mileage of 28,275 miles ( see photograph attached). It should be noted that we have no record of failures or replacements having been carried out on the near side axle shaft, therefore it must be assumed that this bearing has completed a total of 136,506 miles to date. CHASSIS. 4.B.50. The off side ball race failed at a total mileage of 19,541. A new ball race Hoffman 345 was fitted and the holes in the ball cage elongated .100". The total mileage of this ball race was, 8,680 prior to the car being stored at Shardlow. CHASSIS. 9.B.V. There has been no rear axle shaft ball race failures on the above chassis during its total mileage of 59,283. The only alteration to the rear axle was a temporary measure which was to Hs{Lord Ernest Hives - Chair}/Gry{Shadwell Grylls}'s instructions as follows:- - continued - | ||