Overhaul

Preparation

This may sound frivolous but we went through the trouble of cleaning the motor and under carriage before beginning the job. Our experience has shown that this simple step goes a long ways toward reducing future headaches.

Transmission Removal

I'll skip the gory details of the transmission removal and leave you with this one warning: the torque converter contains a surprisingly large quantity of fluid which can easily and quickly fill a size 9 1/2 shoe.

Disassembly and Inspection

Once we had the transmission removed and on a work surface, Wayne began a lightning quick disassembly. I had to ask him to slow down in order to take photos. As he worked, Wayne inspected each piece he removed, searching for the cause of the transmission's slipping. It wasn't long before the problem was located. Some of the clutch plates in were severely worn. Some of them didn't even have any friction material left; it was metal on metal. We also intercepted a future problem with one of the planetary gear cages. There were hair-line cracks in the welds that secured the gears' shafts to the cage. That was the extent of the problems. The AutoTrans Inc. rebuild parts would take care of the clutches. Re-welding the planetary cage took care of the cracks.

What struck me most about Wayne's work was the amount of time he spent cleaning every single part, including nuts and bolts. When you do this work for a living, you have to make sure everything gets done right the first time. A parts washer is now on my list of things to buy for my garage.

The valve body, the "brains" of a non-electronic automatic transmission, was removed and set aside for the time being.

The torque converter was sent to Pro-West in Port Coquitlam. They're AutoTrans Inc.'s B.C. office. After asking us about our Jeep, they decided that a custom-built torque converter would be the best choice.

The disassembly begins.	Looking at the filter, it was apparent that there was some kind of damage in the transmission.	Bits of metal are visible in the top right of the photo. Not a good sign.
The valve body was set aside. We would deal with it later when we stripped it and re-assembled it with the TransGo shift kit.	Near the end of the disassembly, Wayne spotted the cause of my transmission's problem.	Some of the clutch discs were completely worn. The top clutch is a new one, the bottom ones are from my transmission. Notice that the bottom right disc has its friction material worn off, leaving bare metal.
Some of the clutch pressure plates were burned from the friction. The new one is on the left.	A couple of the welds on this planetary gear set had hair-line cracks in them. It was lucky that we spotted this while we had the tranny apart. It could've caused an expensive problem later on.

Re-Assembly

We began by placing the new clutches into a bucket of fresh ATF. While Wayne began the re-assembly, the clutches would absorb the fluid as they soaked. New pressures plates, gaskets and seals would be used in the re-assembly to bring the transmission back to its original performance level.

Putting the transmission back together was a little more time consuming but it went together without problems. Every now and then Wayne would test the operation of various valves by pressurizing some ports with an air hose. Better to identify problems then instead of later, when it was back in the Jeep.

Every piece was thoroughly cleaned before it went back into the transmission.	Each component was cleaned up with emery cloth where necessary.	We used the lathe to remove a ridge that had formed from wear and tear.
The clutches were allowed to soak in transmission fluid prior to their installation. This allowed them to absorb the fluid and swell to their operating thickness before we used them.	A clutch disc with friction material. This will be a novel change from the past year of abuse.	Another welcome change will be the re-welded planetaries. The welds will be ground flat before we put the the planetaries back into the tranny.
Wayne is re-installing the planetaries.	Grease was used throughout the assembly to hold pieces together and provide lubrication during the transmission's initial use.	Installing one of the clutch bands.
An air hose was used to pressurize some of the circuits to test that the various valves were working correctly.	Before installing the torque converter, we primed it with about a litre of ATF.	Once we made sure the torque converter was fully seated on the pump splines, we rolled the transmission under the Jeep for installation.
The aluminum cooler on the left is for the steering pump, the black one is the new external transmission cooler.