have a turbo 350 in my 77 and after it sits for 7-10 days the tranny starts to leak from what looks like the dip-stick port. I just recently replaced the AFT mount and it sit out in my driveway on jack stands with a floor jack supporting the tranny while the Aft mount was being replaced.

After replacement is when I started seeing the leak so I thought I might have cracked the pan ( Pan was supported by floorjack with piece of wood between pan and jack). I replaced pan and changed dip-stick O-ring and it was good to go I thought. 7-10 days later noticed large puddle under car and fluid everywhere ( it even jumped over to my exhaust) Before all this happened I started to hear the tranny making a noise like it was supercharged. I am just looking for little in-sight before I go forward with replacing the pump.

I am gonna change dip-stick first since I hear a chrome dip-stick could be the culprit.

Any in-sight would be greatly appreciated


Sometimes it will move right after start and other times it pulls like it has a clutch. The last time I took it for extended drive it started out rough and eventually ran fine. 4 hrs later after it sit again it was like I was clutching it to get it to move and after it warmed up up it was fine again.

 

You may check around the kickdown linkage. I had that problem once.

 

Yes there is an o ring on the cable.

 

I had changed what I thought to be every seal on my TH350 and still had a leak. Turned out to he the o-ring at the 1-2 Accumulator. Here's a link that may help...

http://th350.netfirms.com/browser.htm


http://books.google.com/books?id=buw...xa8kUnhXaXMV-Q

 

the reason you are noticing the leak after a period of a couple weeks or so, is due to the converter draining back in the pan. this raises the fluid level above normal in the pan. this is causing your leak, and probably around your dip stick tube as you suspect or around your kick down cable. when you start it up, it fills the converter out of the fluid in the pan and the process starts all over again.
chrome dip sticks are notorious for leaking, that is correct. so, you are probably on the right track.
a couple years after your trans was born, GM started putting 2 orings on the kickdown cable to help this problem. and eventually, they did away with the orings all together, and went with a "boot" style seal on the kick down cable, and then on the dip stick, in an attempt to eliminate this problem. and it worked. you might check into upgrading to this boot style dip stick tube. i am not sure if it is available for a 350 or not, GM upgraded the 400 in later years, and i think all 700r4's utilize this design. every transmission uses it now. but as for the 350, i am not sure sure if anyone every thought of upgrading it or not.

probably worth checkin into. but even without the boot style tube, you can stop the leak. it is very doable.

i could be your accumulator, but usually they only leak while driving, when the accumulator is being used.
make sure, in an attempt to stop your leak, you are cautious about the use of silicone to solve your problem. generally, it will not. it will just make a mess. for the most part, silicone and automatic transmissions do not go well together.

as far as your whine and slipping is concerned, that is probably the pump starving for fluid. a leak around the filter, restricted filter or low fluid level can cause it.
keep in mind, if it dumps out fluid after sitting, then it will be low after you start it.
hope this helps.