[TRADERMIKE 2012]

Mikes Reply:
I started this thread 8 months ago and I would like some input from those people who know all about the Pontiac th 400 Trans. only.
First, I needed to read all about the th 400 and watch many videos to build my confidence to rebuild this Trans. with my roommate. I bought a rebuild kit from B+M products plus some additional parts on the net that are needed for a fresh rebuild. I also bought the tools needed for the job that I did not have. First to refresh this story, I ran over a root under an asphalt driveway that a tree root lifted the driveway enough to damage my Torque converter as I slowly moved forward the Trans. bottomed out raising the drive train up. It turned out that the T.C. had a half a dime size chunk missing out of the front Bearing in the Hub that enters the front of the pump area. This is a leak and so I had to replace the T.C. Then, I installed this new T.C. and tested to see if I could fix the other problems that had occurred internally. I went 300 miles more and tried cleaning the valve body, Govenor and Modulator, plus the inner screen and Accumulators to some positive results. Eventually, I lost the forward movement completly. I then decided to buy a rebuild kit and here are the results so far on the tear down:

Upon pulling the Pump we found that the seals between the Front Drum and the Direct Drum on the Stator Shaft were damaged. One completely in half and lodged in the Direct Drum forward area and the second one was in place but not clamped together. These are the Metal Factory type "o" rings. Thus, there was loss of Hydraulic pressure, I can say only that I have Reverse but no Forward gear at this time. Secondly, we found that the Intermediate Clutches are worn and all need replacement. Since we disassembled the Trans. in complete assemblies, we have yet to break it down into single components. No other damage to the outer Drums is noted and the Forward Band needs to be replaced. The rear Band looks good. Since I have the B+M rebuild kit, I want to know if I should replace all the Bushings or only the ones that I think need replacing like the Pump bushing as a matter of that I was told to in my reading. Should I keep the rear Band since it is in good shape and the factory one is better than the one that comes in the kit or so I have read? Also, I bought a new Oil pump Gear for $12.00, should I use the new gear or not? At the rear of the Trans, I bought a Bushing that goes with a Torrington Bearing. I also bought Torrington bearings for three other places. This is a 376 - 430 HP motor, A 428 ci HO Pontiac Engine, Stock, with a "041" Cam and New Hydraulic Lifters, timing gears and chain advanced to 108 degrees for super tune. Plus, New Chrome moly, HD Push Rods. Headers and Tri-Power intake with cold Air induction. I will check my Tolerances while rebuilding each section at a time and while assembling. Do I need to be careful with the Front and Rear end play and just build the center as it is or should I be very careful with the middle two areas Tolerances. Some say that there are four and the factory calls for only the 2, front and rear?