I have a 96 Toyota Avalon with the 3.0L V6 engine, it had over 150K miles on it. I have been using GTX HM oil on it for the last 3 oil changes, total miles driven is about 16K. On the last (the 4th) oil change a little over a month ago. I got a hold of some old Havoline 5W30 oil (not the DS) for a good price. So I decided to try it out on the Avalon. The Avalon had a slow oil leak for a long time, just a couple drops over night here and there. But after this recent oil change with the dino Havoline oil, the car started to leak oil a lot more and somehow, the driping oil start to get onto the exhault pipe and start smoking after the engine is off. I don't really know what happened, whether this faster oil leak is due to the switching to the regular dino oil or not (especially the old havoline with a high molly content). Can anyone shine some light on this subject please. Thanks.