Oil stop leak

[Number4]

ATP-205 highly recommended by Scotty Kilmer.
Or Blue Devil, which for years has sold an expensive but highly successful head gasket fix product. So is their stop leak good too?

Anyone have personal use?

My car has 226k on the original engine and trans. I’m not pulling the engine to get to a rear main seal. Uses 1qt per 3k miles as listed in a previous post.

 

[BKennedy]

I don't think that stop leak stuff will work for a seal on a moving part. I could see if filling a gap on a fixed part, like a valve cover gasket, but not for a rubber seal for the output. The shaft rotates rapidly in the seal so it would wipe off any sealer.

 

[Number4]