My son's 125K+ mile SL1 has been leaking transmission fluid, but has just started getting much worse. I took a quick look underneath and it appears to be coming form the area of the filter, transmission cooler lines and a sensor. I'm guessing it is one of the cooler line fittings since it appears to be wet near that area. Question: Is this a common leak and if so, will tightening the compression nut on the cooler line stop it or is there an O-Ring in there that must be replaced? Also, it appears that space is at a premium in that area so swinging a wrench will be tough. I'm assuming that if the trans filter is removed there will be enough space, but just wanted to check with someone who may already have done this job. Thanks in advance for your thoughts and advice. The car has been extremely reliable and have only replaced a muffler in addition to regular maintenance items in the 18 months he has driven it. Bob