On-the-fly Oil Change

The vehicle, perhaps a truck with extra room under the hood, has fittings for dual oil filters and a valve to select one or the other. Two oil reservoirs are fitted: one empty and the other containing fresh oil.

When the time comes for an oil change the driver parks his vehicle, overnight or perhaps just for lunch, and after a few minutes to allow residual oil to fall back into the pan an electric pump evacuates the crankcase into the empty reservoir. Upon completion fresh oil is pumped from the other reservoir to the crankcase, and the spare oil filter is valved into service. This can all be automated.

When the vehicle does go in for service both filters are changed, the old oils pumped out and the system refilled.