A-833 - 4 speed - sticking and grinding at times

I agree with RC. If you're not trying to shift it with your foot on the floor it's probably not the shifter. First thing I think of of is clutch adjustment. If the disc has a marcel spring in it you may need up to .080-090 clearance at the disc.

The other thing I can think of would be gear lube. Oven ever been a fan of ATF in a gearbox. Gear oils are way too good today to bother with ATF.

Ok, just reread the post. You have gear lube in there. Quite odd it likes to be hammered on to shift. I doubt that is a synchro deal but could be.