Aussie79

I have a stock TH350 trans in my 79 that works perfectly, shifts right when it should and the shifts are so smooth that on normal driving you often cant tell the shift occured. Obviously I dont want to remove or tear down this transmission when it works so nicely.

Now the leak, with the engine at idle and the fluid levels normal at operating temp it drips about once every 30 seconds from the side of the exhaust shielding just rear of the bell housing, it drips from the passenger side of the transmission and I am pretty confident it is not the seal behind the torque converter because no fluid comes out of the small inspection hole at the bottom of the bell housing. I cant see up the side of the trans from where it is leaking as the exhaust is in the way. What is on that side of the tranny that might leak and what is the fix for it?

Thanks, Dennis.

Tally Ho

When you find it let me know. I have a similar situation with my 700R4 in my 82. I changed the fluid and filter and installed a new pan gasket. The leak is on the right side somewhere in the centre above the pan. No loose or over torqued pan bolts. It leaks while sitting still and cold.

madeintheusa

could be a couple of things transmission lines or the kick down cable seal the dip stick tube is over there as well.

7T1vette

Did the '79 TH350 tranny have a vacuum modulator or a TV cable? If a vacuum modulator, there is an O-ring seal on it that can cause small leaks. Are you certain that it's not a pan leak on the right side/? It might also be a governor cover gasket leak.

madeintheusa

Modulator valve is to the back of the trans but still on the right.

speedreed8

my 79, leaked also right side, it was the seal on the kickdown cable, it has a rubber boot and 1 bolt to hold it in, i had to install a new boot with sealant to get it to stop. it is difficult to reach with the exhaust pipe in the way. and it takes a 10mm wrench for the bolt. good luck.

elealusaf

i had mine just rebuilt th350... put a new dipstick from autozone in. mine leaks from that gasket where dipstick enters tranny. put a little leak loc and works great so far.