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WHY!? AT Pan Gasket Pain

May 28, 2013
WHY!? AT Pan Gasket Pain

Can't believe what a pain this has been. Got everything put back together and the pan gasket is still leaking. Thought I did everything right putting it back together, even used a torque wrench to make sure that I didn't over-tighten the bolts. 

The only thing I didn't do was use a ball peen hammer on the bolt holes on the pan to flatten (or over flatten) them. I'll have my pops help with this to make sure I'm doing it right, then post another how-to. I have a new Felpro gasket on order. It's not that easy to get stuff for a C3 transmission. Here's the part number: TOS18640


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May 14, 2015 11:35
Ford trannies leak....all of 'em I think. My C4 leaks in spite of everything I've done. Drain plug gasket, pan gasket, straightened pan flange, resealed band adjusters (surprised me!) and line connectors, and new o-ring around dip stick tube. I think it stays awake at night thinking of places to leak.
March 17, 2014 14:07
There was a old "TUG" airport luggage hauler at a cannery here in Oroville used to haul pallets of full fruit cans over to a staging warehouse. That thing had a 4 cylinder ford and a c3 trans. Before they governed it it'll pull the front end up like a dragster. But yeah it leaked trans fluid halfway through canning season. They switch to a electric tug and that thing leaks fluid also. From what who knows. Guess the mechanics knows. hydraulics? I have a '05 crown vic p71, was leaking trans fluid. then one day stopped. Makes me wonder.
June 10, 2013 01:55
Hey GG and Davis, thanks for sympathizing! I'm on the path to fix this now.
I fell back on Fel-pro's latest gasket and it's a composite of some time. Feels like rubber, mostly... Then, I asked the Fel-pro rep what was the best way to make sure it didn't leak. He said to use yellow weatherstrip adhesive, aka, "yellow death" (that's what my pops calls it at least) to glue it to the pan. So... that's what I'll be doing. Of course it's over 105 today! Plus, I plan to put my Falcon motor together with pops.
June 5, 2013 01:12
C4 trans, i've had best luck with the old flimsy cork gaskets. a good trans man told me they seal better than a thick rubber gasket. no sealant necessary. i've found that its best to wipe both surfaces as clean as possible, install and tighten bolts in the cross pattern and then add your fluid with engine idling in park.
then, take her for a spin and get the engine/trans good and hot. it'll help seal the pan.
and yes, make sure your bolt holes are as flat as possible. ball peen hammer and a vise work best for me.
May 29, 2013 21:49
Grrrr....transmission leaks are the worst!