TripleD

So I am almost 99% positive I have a rear main seal leak in my 2002. What is odd is it seems it came on real quick. I bought the RX with 104K. I did the tranny pan and filter change immediately and I changed the oil and filter. I used Amsoil ATF and I used Amsoil 5w-30 fully synthetic. The RX now has 116K and it seems it just started leaking about a week ago, before a week ago I may have just had one very tiny drop of oil hanging from the bell housing area. Maybe a drip every 5th time I drove it. Very minor. Now it drips about 10 drops after everytime i drive it. Would changing over to synthetic cause this? I am not sure if previous oil was synthetic or not. Whatever the Lexus dealership would have used. It was serviced its whole life till I got it at Lexus dealership. Also I did seafoam treatment when I first got it. Maybe some of the seafoam didn't get drained? Could that have caused it? I guess I could try some dino oil. If this doesn't work Auto RX, I guess, and if that doesn't work then I guess $$$$$$$ will fix it. Input would be appreciated.

code58

I personally wouldn't use any more "Seafoam" in it. I WOULD use the Auto RX. I believe you're supposed to use dino when you're doing the treatment. Be sure and confirm that before you do. It has cured the RMSL for a lot of people. If I was a betting man, I believe it will do it. Run it for a couple of full changes though. Give it a really good chance to clean any garbage out of the engine as well as soften the seals. I doubt that the car had synthetic used, unless the previous owner specifically requested it (and payed a lot of money for it). Bypass using the dino alone and go straight to the dino with the Auto RX. The synthetic can cause a seal to start leaking because the molecules are uniform, thereby allowing the oil to escape easier. Synthetic doesn't NECESSARILY cause leaks in good soft seals.

C-Stone

Old seals & gaskets seem to stay soft with normal oil (non-synthetic). On a previous vehicle (GM), I used synthetic and had issues with seal leaks. You could use Auto RX, as code58 suggested, or go back to regular oil to see if that cures the leak. Let us know how it turns out.

TripleD

I think I will try some dino oil first and then if no luck use Auto RX. Thanks for the replies.