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).
Mileage test results for 'XXL' oil in Experimental Department cars and its potential as an alternative oil.
| Identifier | ExFiles\Box 179\3\ img066 | |
| Date | 13th January 1932 | |
| -2- Up to date the following mileage has been completed on 'XXL' oil in Exptl Dept cars and no drawbacks have been encountered. 22-EX. (Gear Box) - 7656 miles. 20-EX. (Gear Box) - 4,300 miles. 19-EX. (Gear Box) - 1535 miles. In addition all Brtl 20/25HP cars are now being run with 'XXL' in the gear box (synchromesh) and rear axle. We should therefore soon be in a position to recommend this oil as an alternative to Price's Amber 'A'. Ha/A.J.Lidsey. | ||