Transmission Rebuild

I’m not looking forward to stripping the transmission tunnel. I planned to do the job today. Since it is such a dirty job, I decided to procrastinate doing it until tomorrow.

I started off this morning by cleaning the transmission gears in the utility room sink. I cleaned them with a plastic bristle brush, a brass bristled brush, and some degreaser. The gears came out amazingly clean. After cleaning them, I washed them with water, dried them off, sprayed them with WD-40, and sat them in the sun. The WD-40 was used to displace the water and keep surface rust from forming.

The kit I purchased came with Nachi brand input and output bearings. I immediately assumed they were generic and posted about them on the StangFix.com forum. I learned they are made of high quality steal and are some of the best bearings available. This eased my mind considerably.

The kit came with plastic thrust bearings for use at the ends of the countershaft and reverse gear. I researched the use of plastic thrust bearings on the internet but could not find much information. I posted about these also and someone indicated they are used as other metals do not embed in them as easily. This does not make much sense as they are plastic and you would think hot metal would stick in them. Since the size provided would only work on the reverse gear, I decided to just reuse the copper ones as they are not worn.

I slowly assembled the transmission using my Shop Manual and disassembly pictures as a guide. The parts were not difficult to install. There are suppose to be alignment marks at the ends of the gears (according to the shop manual) but I could never find any. The gears slid together much easier than they came apart.

I’m a little concerned by two left over snap rings. I really should not be as they are too small to fit the output shaft. Additionally, the kit did not come with enough snap rings so I had to reuse one to hold on the speedometer gear. I took pictures of all the gears and installation process (with snap rings installed) so I can remember how everything went together in case I wonder later.

I was able to install the output bearing with a little ingenuity. I placed the entire transmission in the bottom of the refrigerator (yes the whole thing). After a few hours, the cold caused the metal to constrict slightly. I then used a hair dryer on the output bearing which made the metal expand. I was then able to slide the bearing on when I was not able to do so with both parts at room temperature.

The transmission is now complete except for the input shaft. I was not able to remove the old bearing. I think I’ll take it to Vila’s on Monday. Since they are fairly priced, it will likely not cost much to have them do it for me.

The next job I finished was painting the top cover for the transmission. I soaked the top cover in phosphoric acid after cleaning off all the grease. This cleaned off the rust and left a phosphorus coating which does not rust. I then primed the part and painted it with the VMT Cast Iron paint.
The last job for the day was the tail housing. I used an old brush to clean the inside of the tail housing. I then a seal/bushing installation tool I rented from O’Reilly to install a new rear bushing. I then painted the tail housing using the Plasti-Kote Cast Aluminum paint. Once the part dried, I installed the new rear oil seal.