My recently rebuilt M21 had a random ticking noise that I noticed in 1st & 2nd gear. The tranny had to come back out for other work so I opened up the case to take a look inside. All the gears look great but there was about a bb's worth of metal in the oil. The only thing I haven't taken apart to look at is the front shaft & counter gear bearings. I don't recall lubing the front bearing prior to installation as I was thinking it ran in oil. What do you think?
I think you might want to check the counter shaft bearings and the thrust washers. make sure the rear counter shaft thrust washer is not spinning on the case, you have to remove the shaft to check, also did you get all the little roller bearings in there? Hope this will help,if you need more info e-mail me Larry