is long-life oil of relatively high
viscosity for the lubrication of rear axles and
some manual transmissions. Most final drives and many accessories in
agricultural and construction equipment also require gear oils. Straight
(non-additive) mineral gear oils are suitable for most spiral-bevel rear
axles (see gear) and for some manual transmissions.
Use of such oils is declining, however, in favor of EP (extreme-pressure)
gear oils (see EP oil) suitable both for hypoid
gears (see gear) and for all straight mineral oil
applications. An EP gear oil is also appropriate for off-highway and other
automotive applications for which the lubricant must meet the requirements
of Military Specification MIL-L-2105D.