To Craig and everyone following this thread. I wanted to digest this for a day before I posted (plus we've been pretty busy, so this reply is being sent after hours). I know that one complaint with the transmission was the popping out of second gear. Aside from the nasty wear on the cluster gear, we took particular care to address the popping out of gear issue. I had initially felt that his second gear was a bit worn with my first glance. We ran it through our cleaner so that everything would be clear as to wear issues. Although the small synchro teeth are showing some wear, I felt ultimately that it was reuseable. We did not have any NOS second gears on hand, and my stock of used 81A-7102 second gears was more or less equivalent to Craig's gear. The bushing inside the gear was not worn to cause me to eliminate its use either.....the fit on the mainshaft was nice.
So, obviously, we look for any other areas of possible endplay problems relating to second gear and the synchro sleeve. His sleeve showed signs of wear in the splines, so we elected to replace it..........and used an OEM Ford sleeve. We ALWAYS check the endplay of 2nd gear on the mainshaft. Using the appropriate spacer washers, we were able to get a clearance of between .004 to .005" endplay. The factory spec is 005 to 015" so I felt confident that we had that under control.
His main drive gear was in very nice condition. Using the correct thickness snap ring on the ball bearing, we know that we had very minimal endplay on the drive gear.
The next area to check is the endplay of the mainshaft in the gearbox. This is controlled by the rear snap ring on the rear ball bearing, the rear oil baffle, the rear bearing retainer, and the correct installation of the u-joint. Since we installed a nice original Ford OEM universal joint, I feel that there would not be any measureable endplay with the mainshaft.
I have attached a picture of Craig's assembled gearset. If you look closely at the synchro teeth on second gear, you can note a slight bit of wear but, in my opinion, not enough to cause the trans to pop out.
Frank Miller's comment about adjustment of the shifter linkage is worth a follow up. If the shift was not fully into the factory location for second gear operation, it could pop out under deceleration. When shifted into second, the synchro sleeve moves to the rear, covering the bronze synchro ring........the steel synchro teeth..........and right up against the shoulder of the 22 teeth part of second gear. If the shifter linkage of the vehicle (from the steering column, down the shifter rod, the clevis, to the pin on the shift lever for 2nd/high) is not in correct adjustment, it's possible that the trans is not fully seated into its 2nd gear location. I mention this as a possibility......it should be checked out. This is not necessarily the culprit but it is a very easy matter to check this detail.
We stand behind our work as Craig knows, and will do what we can to help make this right. Even if it means bringing the transmission back here to have us go through it again.
Mac VanPelt