[AT] End Play...How Much is Too Much (On Topic)

[Dudley Rupert]

Following is an On Topic issue (think) -
If any of you care to wade through it I'd be interested in any comment you
might have -
Thanks -
Dudley
Snohomish, Washington
Background - A computer-less friend of mine has a Ferguson T020 which had a
Howard gear and a wicked looking 180 degree weld which went all around the
top half of the transmission bell housing.  Several months ago I told him I
would split the tractor and take the Howard gear out (he wants it in a Ford
8N) and, if he found a "good transmission" I would put it back in.  Well he
found a transmission and I have the tractor all back together and it drives
fine and the transmission seems to work fine (e.g., it shifts easy, the
gears stay engaged, there is no transmission noise, etc).
Before installing the "new transmission" I checked the end play on the two
output shafts using a dial indicator -
    The counter-rotating shaft (the bottom/PTO shaft) had at most one
thousandths play -
    The splined shaft (the top/sliding shaft), however, had fifteen
thousandths play.
I checked the Ferguson TO20 Shop Manual - It does not discuss the
allowable/acceptable end play but does state that the bearing pre-load on a
used transmission should not exceed roughly 1 ft-lb of torque to turn the
sliding shaft with the transmission in neutral.  Although my torque wrench
does not go down to that low a value I am sure the transmission meets this
requirement as I could practically spin the transmission using my thumb and
forefinger.  But, my question is just the opposite - is the shaft turning
too freely/is there too much end play.
So I asked an expert who retired a few years ago from the local MF
dealership (fter being with them thirty some years) and he said there
shouldn't be any end play at all.  He suggested there must be shims either
at the front or back bearing caps but, I checked, and there were none.
So I asked the head mechanic at the MF dealership some twenty-five miles
north of here and he just shrugged and said he didn't see any problem with
"excess end play" in the sliding shaft.  He just cautioned me about getting
the bearings too tight (i.e., the bearing pre-load issue) and I said I was
aware of that.
So I checked the endplay in the "old/original" transmission that I took out
and it was ninety thousandths (everything worked fine in this transmission,
it was just the ugly weld scar that warranted its' replacement).
After talking all this over with the owner he said to just put the new
transmission in and not worry about anything so that's what I did.
Question:  I am curious as to what others of you might have done/thought in
this situation.  Incidentally, the back bearing is roller and the front is
ball.