ok....so I bought a used th350 and put it in my car. when I bought it, it didnt have a dipstick, so I went and bought one. I put it in and started the car and tranny fluid leaked out everywhere from the dipstick tube where it goes into the tranny. well, come to find out GM had two different tubes for the th350. one is an "o" ring type, the other is a grommet type. mine is the grommet type, so I went and bought the right dipstick. now, I can start it up and drive it with no problems, but if I leave it sit for more than 2 days it starts leaking again.......any solutions???
thanx!! almost forgot..this is in a 79 z28.....and the guy I bought the tranny from said it was a 79.

 

I have the same problem. I sprayed the area with carb cleaner and gooped it up liberally with Permatex Ultra Black RTV, which stopped it up pretty well. Then I removed the trans the following summer (long story), and siliconed it again when I reinstalled the dipstick tube, but it didn't work as well that time. So I have a spot on my garage floor, and I'm building a Muncie to fix the problem.