Oil and water have low miscibility.

When I desir’d their leave that I might pity him, they took from me the use of mine own house, charg’d me on pain of perpetual displeasure neither to speak of him, entreat for him, nor any way sustain him.

… moreover, there are times of pressure when, to expedite deliveries, cars may be driven in what should otherwise be the running-in period at speeds that do them no good - and over long distances too.

There's only a rough track and I doubt if that jalopy of yours will make it.