In article ,
Andrew wrote:
Cheap oil is not synthetic. Modern cars run at much higher temperatures
than mineral oil can cope with. On old cast-iron lumps it is the wear
on things like camshaft lobes that might be more of a problem if you
use the wrong oil.

Valve train wear on an old pushrod design is due to the higher loading
than an OHC type, and minimised by a suitable additive. Normally ZDDP.
Which can be used with mineral or synthetic. It's not a common additive
these days as catalytic converters don't like it. But you can buy
specialist oils with it, for use in older cars.

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*Since light travels faster than sound, some people appear bright until you hear them speak.

Dave Plowman London SW
To e-mail, change noise into sound.