In a message dated 11/7/2003 12:38:02 PM Eastern Standard Time,
mvheim@studiolimage.com writes:
> I recently unearthed some information to support the
> contention that one should use single-weight oil in the gearbox (30w rather
> than 20w50). 20w50 is apparenty essentially 20w oil stock with viscosity
> improving additives. These additives have their greatest effect under high
> pressure and sheer conditions (as in main bearings) and don't really have
> any effect under splash oiling (as in a gearbox). Moreover, these additives
> break down relatively quickly. In an engine, with frequent changes, this is
> insignificant; but in a gearbox, one would basically be running 20w oil
> after, say, 10K miles. How often do most people change the
> gearbox oil?
> Think about it.
Matt,
Thanks for backing my contention that multi-grade is not the best for the
tranny, especially with overdrive.
Jay Donoghue
73B-GT
66 Mustang
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