I had the same issue,as you can see from my past post, I tried everything several times.... I bet I checked the pans flatness a dozen times! The problem was resolved when I replaced the pan that I knew was ok....

Good Luck..

jc

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"I recently installed a new (rebuilt) TH350 in my 29 and have been unable to isolate the source of a leak at the pan. I have replaced the gasket and set the bolts to spec and still have a leak? Any ideas?

o No apparent housing cracks
o Pan is flat and straight
o Cleaned gasket mating surfaces
o New OEM gasket
o Bolts toqured to 13 foot pounds
o Gasket installed dry per spec"
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