Topic: Transmission pan gasket

[Jeff1967]

My 67' 289 has a C4 auto, Had it serviced and ever since it has leaked. Tried two times to seal it even with a silicon based sealer and while sitting just fine but after driving the next day there are puddles again?? Should I look into another type sealer to try. The first time I just cleaned the parts and bolted up without a gasket sealer but when it leaked I tried the silicon, used new gaskets both times. Might be the pan and not bolting flush??

Any thoughts out there??

JJ

[Soaring]

Sounds like you may have a warped pan.  Double the gasket, and use only a slight amount of Blue RTV.  Just snug the bolts, then from the inside bolts slightly tighten, going toward the outside.  If that doesn't work, you may need a new pan. 

[Jeff1967]

Glen,
I will try your advise before buying a new pan, But am unclear on the bolt tightening advise? The is only one row of bolts around the pan, not sure what you mean about tightening the inside to outside bolts??

Jeff

[Soaring]

Yes, the bolts are on the outside of the pan.  Start with the ones in the  outside middle of the pan and work toward the ends.  Do not overtighten. 

[Jeff1967]

Glen,

Thanks for the advise, one last question: Do I put the light coating of blue RTV on the transmission side or the pan side or both? You recommended using two gaskets, I assume no RTV between the gaskets?? ..Correct??

Jeff

[Soaring]

You put the RTV on the pan side.  Just enough to coat it.  Don't gob it on, and not between the gaskets either. 

[rmodel65]

i would take it apart and install the gasket dry, rtv can make the tranny fluid foam

[Soaring]

i would take it apart and install the gasket dry, rtv can make the tranny fluid foam

That's why I said just a little.  If the RTV doesn't get into the fluid, you won't have that problem.  He has a warped pan, and needs to fill in those tiny places where the pan is not exactly square with the world.  If you read the thread from the beginning, you would realize that he has already tried what you suggest, and it still leaked.