Leaky line

Rumble your right about the ones at Lowes, Ace, etc. not being exactly the same. Theres 2 different angles on flare fittings and to look at them with the naked eye you can't tell them apart. One is 37 degrees and the other one is 43 degrees if I remember right. Anyway you have to have the right one or they won't seal right. The one from the 727 should have worked. If it's leaking from between the 2 fittings thats not good because sealer won't usually help there because the flare is what seals things. Even though it's a new line look at the flared surface closely to make sure they didn't crack it when they made it. It could still be the adapter fitting also if the fitting sealing surface is just worn out. Of course if it's coming out from the trans side of the fitting the sealer should help.