In article ,
Andy Dingley wrote:
Because it's not available in the same 'thickness' as those originally
recommended?

No, it's about viscosity, but not under the same conditions as the
viscosity measurement we normally worry about. It's the "viscosity
for creeping through narrow gaps, when lightly loaded" rather than
"tenacity of the oil film in a bearing, when hot and under high
pressure".

I believe that the fluorinated plastic used for seals in Vauxhalls was
a deliberate move to make them seal better with synthetic oils. These
are the seals that can produce hydrofluoric acid after a fire.

I've heard some say older engines will leak with synthetic, but I've not
found this with my '84 SDI. I did replace the front crank seal though -
but this was leaking with dino oil too. Which was 10-40.

Nor does it burn any more - it will still do one annual oil change to the
next without topping up.

--
*Corduroy pillows are making headlines.

Dave Plowman London SW
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