My transmission is leaking a little bit. this is after they installed a used one. i took it back so they could find the leak and it was resealed. it is still leaking and the repair man told me that it's not a major problem and to find out the exact spot where it's leaking means they have to take the transmission apart. my question is "is this a major problem" and if i bought something from the store like "stops transmission" leak products will it work?

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ez rider