My 240 had a leak coming from the engine area. I was using Wal Mart brand 10/40 dino oil in it. My wife was using this car as her daily driver so I did not have a chance to really look it over too much. I just added about a quart of oil per month to it. My wife stopped driving it earlier this year when she got a newer car. Last March I switched to Wal Mart brand synthetic 10/40. I let the car sit around until July when I began to drive it again. Between March and July I started it up once a week or so but that was it. I have been driving it pretty steadily since early July with not even the slightest drip of oil. Last Friday I checked the oil and it has not budged a bit. With all the talk of synthetic oils making seals fail and increasing drips I was hesitant to make the switch over. Now I am certain the engine runs better than ever. I am guessing the reason for the cessation of the drips would be the swelling agents put into the synthetic oils. Would anyone else agree? I have been wondering if I will realize a benefit from the use of synthetic oil in the oil trap and throttle body? Has anyone actually observed a difference in these areas when switching over to synthetic oils? By the way the cheap Wal Mart synthetic is good stuff. I have used in my truck for some time with great results!