I had a leak on the transmission when I got the car. It turns out there was a crack on the speedo drive and I replaced it and also done the pan gasket (cork gasket) and filter. After a while I noticed that oil was getting through the gasket but I had been transporting the car on a trailer and thought it was from the swaying back and forth on the trailer. After I had the body repainted I replaced the pan gasket again but a week later it was through it again. I replaced it again with lots of gasket seal, made sure the gear box wasn't over full, repaired two damaged treads with heli coils, checked the pan bolts after a week for tightness and used tread lock on them but the oil is still coming through the gasket when the car is idle. The manual says to use dexron 2 fluid but I could only get Dexron 3 equivilent and I presume it's the same thing or do I have to use dexron2?. Is there anything that can be put through the fluid to help stop a transmission leak?.

Thanks.

 

Often the pan gasket rail will get "dimpled" at the bolt holes. I usually try to peen them back flat (use a piece of wood/board to back up the pan as you use the ball peen).

When the gasket rail is dimpled, it overcompresses the gasket at the bolts and undercompresses it between them.

Normally gasket goop isn't required on the tranny pan gasket.

Dexron III covers Dexron II applications.