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).
Engineering memorandum from Vacuum Oil Company Ltd. detailing Mobiloil gear lubricants.
| Identifier | ExFiles\Box 40\4\ Scan330 | |
| Date | 17th April 1930 | |
| Form 0201-50000 VACUUM OIL COMPANY LTD. CAXTON HOUSE WESTMINSTER LONDON S.W.1. AUTOMOTIVE LUBRICANTS DEPARTMENT. ENGINEERING DIVISION. ENGINEERING MEMORANDUM Messrs. Rolls Royce Ltd., Derby. Gear Lubricants -------------------------- Referring to the letter from the above received by Sheffield Office with reference ROY{Sir Henry Royce}/GEA4/EB17430 dated 17th inst., we regret that our 1930 Mobiloil Chart of Recommendations is not yet available, but have pleasure in giving hereunder a list of our gear lubricants, together with descriptive matter:- Mobiloil "C" A dark coloured, general purpose gear oil having a Specific Gravity of .945 and Cold Test of 25°F with a Viscosity of approximately 167 secs. Redwood at 200°F, 778 secs. Redwood at 140°F and 3519 secs. Redwood at 100°F.{Mr Friese} We recommend this oil for general use in gearboxes and back axles during summer. It is equally suitable where the wheel bearings are lubricated from the axle case. It is also suitable for grease gun chassis lubrication. Mobiloil "CW" A dark coloured, light bodied gear oil principally recommended for winter use in gearboxes and back axles where it is desired to reduce the fluid drag in cold weather and obtain an easy gear change when cold. The oil has the following characteristics - Specific Gravity .935, Cold Test 10°F, Viscosity at 200°F, 91 secs. Redwood, 335 secs. Redwood at 140°F and 1268 secs. Redwood at 100°F, these figures being approximate. This oil is also sometimes recommended for summer in gearboxes and back axles where there are small oil passages, close fitting gear housings or remote speedometer drives which make it desirable to use a more fluid gear oil than normally employed. From the information received recently from the Vacuum Oil Company, New York, we understand they are recommending Mobiloil "C" summer and Mobiloil "CW" winter for the majority of back axles in American cars using Hypoid gears. It should be noted that Mobiloil "C" and Mobiloil "CW" are compounded. Cont'd.{John DeLooze - Company Secretary} | ||