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Need 727 Trans pan improvement suggestions

Ya i had my tranny rebiult also,had the hard gasket also,im pretty sure its leaking between the pan and tranny,but im going to recheck this winter,i replaced the shifter seal and its fine,but i will check the filler tube o ring.seems like everytime i try and fix it,it will leak in a different spot
Thanks
Paul

One more place to look for a leak.The low/reverse band pivot shaft has an O ring that can leak,mostly overlooked in most cases,the shaft exits the back of the case.Rather than removing the transmission to replace it ( you have to take everything out ) you can remove the valve body,loosen the reverse band remove the five bolts on the transmission extension housing and rotate the housing then you can remove the shaft out the back of the case.Depending on the year there could be two O rings,early transmissions only had one.
 
Pan gaskets properly installed don't leak. The 518 pans work great but do require an extension for the filter. I use the run of the mill cork ones, no sealer. DO NOT OVERTIGHTEN, #1 reason of pan leaks. Most leaks are above the pan that drip down. How to find the leak.#1 Clean with brake clean and blow off with air until the trans is dead dry. #2 puff baby powder on dipstick tube ,bell housing opening, lines, rear band anchor pin, valve body case seal,etc. #3 Do not start, let it set. #4 look for the powder to become dark and damp. Many leaks will occur while sitting do to the fact that the fluid level is higher. #5 No leaks found yet?, Start the engine and watch again. I will bet you can pinpoint 99% of trans leaks this way.
Doug
 
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