Bkay, the Singer 201 manual does indeed say to oil the hook drive gear. This is one place where a little Tri Flow grease is good to use.

Cari

Unfortunately at this point I can't alter my post. Wish I could as it was way too general. My apologies.

No, I haven't read the manuals for 101s, 221s and 401as.

This subject of grears or oil turn up now and than. For the 201s, I think the early ones called for oil on all sets of meshing gears, actually every where except for the 201-2 and only calles for grease on the gears behind the hand wheel near the potted motor. If you look at a late 50s manual it might say something different than an earlier 1930s manual for the same model. For these gears there's no absolute need to use grease; oil often reduce friction better in coparison tests. The advantage with grease is it lasts longer and it has it's advantages. There are a few more current tests on oils with or with out teflon, syntetic derivatives etc, verus grease and the liquid oils compared well. That said, the right grease will work well. I have tested my 201 with greased gears versus teflon oil, and it turned noticeably lighter as the oil was added to the tree sets of meshing gears.