"Twit", use 75/90 synthetic gear lube oil.
Works great. The only thing is, you need a good
gasket to contain the synthetic lube oil.
I put the oil in before re-assembling the motor.
The motor is super quite.
Terry K

It's kind of hard to tell.
My objective is for the gears to be about a third
in the lube oil.
I guess that would be 1/3, or a tad more, full.
It's hard to get the oil just right,as the gears tend to
fall out when you try to put the motor back together.
One of my motors has a fill hole on the top, but, what I don't
like is that it is hard to get 75/90 in the small hole; then
again you are not sure how much you have in the case!
I found anything lighter than this oil grade tends to
a noisy(er) motor.
Terry K

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