Built my own transmission this time and at first the first to second shift was good but it would not shift into third unless you took your foot off the gas pedal. Dropped the pan to find the filter was loose. In putting the filter on the bench and looking at the bolt in place with the spacer, I saw it was not long enough. Not only was the bolt to long, the "spacer" was to short. I put the filter back on with two O-rings on the tube (tube is plastic) and the filter was tight. Now the first to second shift is firm, but the shift to third (high) will only happen at part throttle only ( not at full ). Is it because of the plastic filter-to-case tube ?
The filter bolt is designed to let the filter move up and down with the fluid level. It's a special shouldered bolt. I hope you didn't use a bolt to rigidly mount the filter. Using 2 O rings is a good idea. Make sure the filter tube is all the way into the valve body. They can be a bear to get in sometimes.
The bolt I used came with the longer tube. Anything wrong with using a standard length tube ( and bolt ) with a deep pan ?
Ya, there is a special tube that is longer that goes with the deep pan, and longer bolt/spacer deal. Get the right parts in there first.. http://www.jegs.com/i/Derale/259/14...NKTssFE73Zfe8mm3ImdP5s0EtiO8Zn6ITChoCYNnw_wcB JW
Have the long tube (plastic type) with the spacer in it now. I was wondering if it would do any harm if I swapped in the short tube ( metal type) with the deep pan. My last transmission had the factory depth pan and it shifted well.
Mike, With the deeper pan, the extended pick up is necessary unless you want to risk uncovering the filter and sucking air. There is also a specific filter bolt AND spacer that go along with that extended pick up. The filter has to move up and down with fluid level. Those specific parts allow that. Like Jim said, get the right parts in there.
Michael, Put a 300 psi pressure gauge on it, and see what is going on. I suspect that if you can't get high gear with a manual valve body at WOT throttle, but can at part throttle, your overpowering the direct clutches. Probably due to a hydraulic issue, which will show up on the gauge. http://www.amazon.com/Advanced-ATD-...0&sr=8-1&keywords=transmission+pressure+gauge I assume we are talking about the car with the supercharged Tomahawk in it? JW
Yes I will try the guage route after I swap to the other pan configuration. Since the guy that has built my transmissions in the past is not longer around, I built this one myself. I have a bunch to learn and this is the best way.
Should have the gauge in by Thursday and have the line pressures. Still will not shift into third (high) under power. Cruse is fine Have had the pan off three times now and changed the filter each time and about wore out the adjuster on the cable going up and down. The fluid is clean and there is no slipping.
Line pressure is/was : Park- 50 PSI Reverse- zero Low-50 PSI 2 nd- 50 PSI High- 40 PSI should be 180-200 all the time. All this time chasing my tail and it looks like a bad pump.
After tear down I found another issue. Put the new pump on (six-bolt) and it went together better than the older eight-bolt did.
Good luck with it Michael.. I assume you replaced the smoked direct clutches.. the reason it would not go into high at WOT is because of that low pressure.. the TH 400 is a stacking clutch trans, it "shifts" as another clutch is engaged. At that pressure, no way the high gear clutches would engage with your power, so it seems like it "won't shift. Zero pressure in reverse typically means a sealing ring is missing or out of place. Defective/worn out TH 400 pumps are very rare, don't know that I have ever seen one.. but the pressure regulator boost valve being worn out is common, and there are readily available parts to repair that issue. I would hope those parts would be in you replacement pump. JW
I looked things over and have it back together. Mistakes made by a first timer. I just found it odd that the guage went to zero, but the car still backed up.
Changed the front pump and started it. Have only backed it out of the garage and pulled it back in. It felt right but looking at the guage I just installed has me alarmed. https://www.facebook.com/michael.evans.9083/videos/10153563712379277/
I don't know anything about manual valve body TH400's, but I'd be curious to know what is done in place of the vacuum module? I could see if it was missing something related to it that the line pressure would go away, but I've never had a TH400 apart so its very much arm chair speculation.
You put the stem in as normal then you put an aluminum cap over it with the correct gasket like you would a vacuum module and clamp it down with the factory "fork". I guess I could have it in backwards. Easy to check.
I have been looking for almost two days on both forums and U-tube. I have not even found a reference to the issue I have. I did get a good picture of the red plug used to remove the vacuum module. looked into it, you can not put the stem in backwards.
Dang Michael, you're have quite the challenge with this one. The only thing I can offer you is some encouragement. Keep after it and you'll get it figured out. Robert
