Late last fall I was starting a job close to home, just 2 miles away. With winter setting in I thought it might be a good idea to switch over to synthetic. Went with Mobil 5-30 and an M1-102 filter. My T had 107K on it at the time. About a month and half ago I was coming up on the 5K OCI. One morning I came out and found oil on the driveway under the truck. Nice new grey pavers! I wiped everything down and drove it. The leak was fom the rear main seal. I was really freaked out. Finding the time to deal with it myself is not easy lately. Giving it out is painful to think about. The few times, except once, that I had work done I ended up miserable. I really hated the thought that the seal was toast. Anyway, I dumped the Mobil 1, then went with Valvoline High Mileage 10-30. Within a day I was told to get rid of it. Seal swellers are bad, so I was told. Dumped the Valvoline and went with Castrol GTX 10-30. Within 100 miles, no more drip. At that point I started an Auto RX treatment. Now, 800 miles later, it's bone dry!

It's been a lesson learned. I won't plead complete ignorance here. I'd heard warnings before. But, for every one warning, there were ten tales from others that claimed to have added synthetics at 150K with no problems. Maybe it's true. Not for me though. I don't have that kind of luck. <img src="/forums/images/graemlins/shiner.gif" alt="" />