C6 not shifting properly

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Jun 16, 2005 | 12:49 PM

elb

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Joined: Jul 2004

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C6 not shifting properly

I installed a C6 in my 1980 F350 with a 460 ci motor. I installed a B&M shift kit and shimmed out the main shaft end play. I flushed out the torque converter, replaced all the seals and gaskets. I followed the manual when reassembling using all torque etc.The transmission works fine when shifting manually. Does not up shift or down shift very well in drive. When I open the throttle transmission does not kick down. There is plenty of fluid, good vacuum and cooling. I was wondering about adjusting the modulater valve and maybe the intermediate band. I was wondering if there was something I missed during assembly.
thx
elb

Jun 16, 2005 | 07:43 PM

mark a.

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Joined: Mar 2004

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The only way to flush a tc is to cut it apart and clean it out then reweld. If there is anything in it it will go right into your trans. Remans are dirt cheep. Also anything in the lines from the previous trans will end up in the trans as well.The output shaft needs to be cleaned out too it holds a lot of fluid. I always leave the return line off of the trans & let it pump into a bucket till it pumps a few qts out just to be sure. Some people will get away without doing all of this, but i don't have that kind of luck. I would start with the shift modulator though.

Last edited by mark a.; Jun 16, 2005 at 07:46 PM.