Vehicle power transmission having fluid-tight enclosure accommodating lubricating points and storing lubricating oil delivered from mechanical oil pump

A power transmission system for a motor vehicle, in which all of rotating elements thereof are stopped upon stopping of the vehicle, and which comprises a lubricating device including an oil sump for storing a lubricating oil and a mechanically operated oil pump which is driven by one of said rotating elements to pressurize the lubricating oil received from said oil sump and deliver the pressurized lubricating oil to predetermined lubricating points within the power transmission system, wherein an improvement comprises:

• said lubricating device having a substantially fluid-tight enclosure in which said lubricating points are disposed and which stores, in a substantially fluid-tight manner, a mass of said lubricating oil pressurized by and delivered from said mechanically operated oil pump.