"Chris Kantarjiev" <cak@godzilla.studio.sgi.com> writes:
> I believe the oil vs grease distinction was important in "the old days" when
> grease had a tendency to harden and separate after a short while (take a look
> inside your wiper motor if you don't know what I mean!). That just isn't the
> case any more, and I feel perfectly comfortable (and much cleaner) using
>grease
> in my trunnions. You could, too.
My understanding is that oil is preferred because it doesn't displace.
The difference between the threaded joint of a trunnion and something
like a bearing race is that in the latter the grease is continually
being redistributed where its needed. A threaded joint will quickly
displace the grease away from the load bearing surfaces and will have
no tendency to return. Once it's squoze away from where it's needed
it will stay squoze away and you have metal-to-metal thenceforth.
Oil will flow back to where it's needed.
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