Has anyone tried Blue Devil Rear Main Seal Stop Leak?

Blue devil was used on a 2003 4x4 transfer case with 200,000 miles on it. New synthetic oil had just been added for that mileage service and the rear seal started leaking almost instantly. Weird!
Puddling was small but very noticeable after the vehicle sat overnight. For a few weeks the driveway needed to be cleaned every day. Being a Toyota it was an 18 hour job according to the time rate book. The transmission shop, really not wanting to do it mainly because of how much it was going to cost me, suggested trying Blue Devil. After reading the instructions the proper amount was added and the recommended 100 mile round trip was driven. I thought maybe the synthetic oil, being new, was just too slick for the seal to hold and I didn’t have high hopes. It was a shocking miracle that there wasn’t another drop leaked. Oh, a question Are you using synthetic motor oil?

cruiser said

Looks like the rear main seal on my 225 slant is bad, and my understanding is that the engine must be removed to fix it. YouTube has a number of videos of guys using Blue Devil rear main seal stop leak, and most reviews are pretty good. Has anyone on this forum ever used this stuff on a slant six? Did it work? For how long? Will it screw up your engine in the long run? Any and all please weigh in with your opinion. Slant Six Dan, if you're out there, what do you think? If you listen to the YouTube reviews, the stuff seems like a miracle cure - almost too good to be true. Thoughts anyone?

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