All kinds of dire predictions and warnings over not using exactly the right kind of branded/specified oil.
Out of interest, has anybody ever encountered an engine failure or premature wear problem absolutely proven to be directly caused by the 'wrong' oil?
Not the wrong viscosity, but a fully or semi-synthetic that simply does not have the appropriate manufacturers' approval label on the can.
The diesel Vauxhall that I'm driving suffered a turbo failure and came in on the back of a truck, with no oil in the engine.
The customer gave it to me. I replaced the turbo, filled up with oil and 5yrs later I'm still driving it. On the basis that it survived being run with no oil, I'm not sure that running with the wrong spec. oil could do anything to it at all.