For military ground vehicles it is essential that a multipurpose gear lubricant be available to reduce logistic problems and eliminate chance of error in field operations.
In order to establish new performance requirements on which to base any change in the current specification, an extensive program of full-scale field and laboratory tests has been carried out by the Ordnance corps for several years.
The results of this program clearly show that increased severity in truck operation may be met by new additive formulations without sacrificing other characteristics, but requirements for extreme activity to satisfy high-speed, shock-induced scoring may have to be held to a reasonable level to avoid damage to gear train components by deposits and corrosion.
From data available to date, it is clear that much can be done by the gear manufacturers to reduce the extreme pressure activity requirements through the use of chemical surface treatments. This in turn will provide a basis for the formulation of truly multi-purpose gear lubricants.