My wife's '92 SL1 w/automatic had slowly been leaking transmission fluid\nsince last winter... probably about a quart over the past year. The\nrate seemed to pick up now that cold weather had set in, so I decided\nto do something about it.\n\nA quick orientation: Unlike the classic 70's automatic transmissions that\nI had experience with, the Saturn's automatic has a pan on top instead of on\nthe bottom. And a little bit of investigation revelaed that the fluid was\nleaking out around the edges of the pan... pretty much everything underneath\nthe seam had a thick layer of grime and ATF on it.\n\nRemoving the pan is not so bad. First I had to remove the battery and the\nbattery tray... there are two bolts that are removed from the outside\nof the wheel well and two that are on the inside on the top. The air intake\nis also attached to the battery tray - rather than unbolt this, I just\nunhooked the whole air intake from the air filter and removed the intake\nand battery tray as one piece. It was still held on by a wire to a sensor -\nthe air mass sensor?\n\nThen there are over a dozen bolts around the perimeter of the pan-top. Many\nwere finger-loose, a sure sign that the seal probably wasn't working too well\nanymore. I cleaned away a dozen years of grime from pan and surroundings.\n\nThere's also an electrical harness that plugs in through the top of the\npan. A snap on cover is removed to reveal a single bolt holding that on.\nEasy to take off.\n\nRemoving the pan revealed a "cooked" gasket. The edge on the engine side\nwas hard and flaking away. The other side came off in one piece.\n\nThe inner guts of the transmission looked brand new. I'm sure there's some\nwear because when I've changed the ATF there's always a little bit of shavings\nin it.\n\nI probably could've bought an "official" Saturn gasket to replace the cooked\none, but it was Sunday afternoon and the parts desk wasn't open, so\ninstead I just used some RTV silicone gasket compound to make my\nown, after carefully scraping off all the cooked pieces and degreasing.\n\nSeems to be holding up well so far today... the leak, if not completely\ngone, is way smaller than it had been. There's also an O-ring that goes\naround the dipstick tube, I should replace that just to make sure that nothing\non the top will leak for a while longer, but I haven't gone to get the O-ring\nyet.\n\nHow long do RTV silicon gaskets hold up for? Am I probably going to have\nto repeat this before the next twelve years are done?\n\nTim.