Castrol Classic D140 is a straight (mono-grade) mineral oil-based transmission oil for most types of gears. A mineral oil with a low content of additives specially adapted for vintage vehicles.
Castrol Classic D140 does not damage sensitive materials and yellow metals such as bronze and brass. Can also be used with advantage in steering gears where API GL-3 is required.
(NOTE: Not suitable for hypoid gears that require higher API GL class such as: GL-4 or GL-5.)