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th400 problems

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Old Jul 8, 2012 | 12:13 AM
  #1  
matt01ws6's Avatar
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Default th400 problems

70 chevelle ss, 496 stroker not original, th400 is original from the car. since i built this car right after my dad passed away i have no idea what is really done to this transmission. i kno it was rebuilt and never used it has sat in our barn for the past prolly around 35 or so years on gravel and had very little fluid in it when i pulled it over to the garage to check out. pulled pan everything inside was shiny and looked all brand new in a way. i kno it has a old B&M shift kit had a b&m deep pan but leaked so i got a stock size one now.

so heres the issue i have never built a car at this level, the motor is VERY strong and extremely built. power est around 600-700 hp range. so i clean out this th400 really good before i hook it up. fill it up w a nice amount of fluid. works great and holds the power idk how but it does, my problem is everytime i test drive the car it will not downshift or upshift on its own. i pulled the modulator it works fine. but the governor has clips holding it from opening. if i remove them will it fix my problem or no? also everytime i test drive it, after just like 2 mis of driving it will start spitting fluid back up the dipstick tube. im on a very tight budget and if anyone could help answer this it would be great thanks guys
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Old Jul 8, 2012 | 11:02 AM
  #2  
72blownvert's Avatar
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If there are clips on the gov then it was turned into a manual shift with the clips off it should shift w/modulator hooked up.The fluid spitting out could be the breather is plugged from sitting so long.I would also put that deep pan back on the more fluid the better.
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Old Jul 8, 2012 | 12:02 PM
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matt01ws6's Avatar
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I switched the pans because the deep one had small cracks in it. I'll get another one I just didn't have the money for it at the time. I'm pulling the gov out right now and pulling the clips. I'll clean the breather again too and see what she does. Thanks
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