Show me proof of where its crap and I might change my tune but I doubt you will.
Ive done Nearly 40k in my 325i now on magnatech and its not grenaded its self, has no oil consumption between changes, looks the same colour inside as when it did nearly 40k ago, still sounds the same and I would be willing to bet there no wear to the cam or rockers.
Even with me driving it!
Ask Pete was he uses in an M20 Simon, and what he has been for the last 30 years!
And don't come at me with tyre analogies, that's totally different.
And Brian, if an M20 has poor oil flow to the rockers/cam the it needs to come apart to be fixed, not limped along on some thinner oil.
Cure the issue not mask it!
As I said, there is NOTHING wrong with using a 10w40 semi if changed often on a heathy engine.






