Only time you need to add oil to that, as long as the trans is
up to snuff is when you've freshly rebuilt it.
The old Bridgeport milling machines has zerk fittings for all
of the ways. Many mistakenly greased those and starved the
ways for oil. There are special oilers for adding way oil and
there were also some automotive oilers that were made for
zerk fittings. Most were plunger type which put pressure on
the fitting as you pushed the oil in.

DG

Denny G
Sandwich, IL