Hello, I have a 72 skylark with a buick 350 and th350. I had some shifting problems and changed the vaccum modulator last year. I would like to trace the source of these leaks, and would like to know how severe they are. https://ibb.co/dANFW5 https://ibb.co/bXJ0yk
You need to actually jack up the car to get under the car for pics. No way ANYONE can tell what/where leakage may be coming from.
The pictures are useless in answering your question, sorry. The most common leak points on the THM350 are, the downshift cable O ring seal at the transmission, and the dipstick tube O ring seal. Not to leave out the obvious pan gasket. If it is over tightened, it can distort the pan rail, and it leaks. There is an O ring on the modulator as well, did you replace that? The best thing to do is to buy some engine cleaner and thoroughly clean the transmission case and pan area. Then dry everything. Start the engine and look for the leaks.
