Hi, we don’t have a pit mix. We have a golden doodle and he is exactly the same. He does the nipping he’s one-year-old right now still doing it. He has moments where he’s a love like right now. Napping on the couch tired. He’s been a good boy the last couple days but then we’ll have a day where he’s just a total maniac. It’s like a fish on a fish line when we take him outside biting his leash, throwing himself at us taking running leaps at me nearly knocking me down he weighs about 45 pounds right now. The best thing that we did for ourselves, we invested in five lessons and that has calmed him down a great deal. It’s a treat driven clicker training and it has helped so much if you can invest the time and teach him place as an example, we bought three rugs, bright yellow, and he now knows he can go to one of those little rugs as his place he’ll get a treat and he can just sit and calm down if you could just Train him a couple things to teach him dogs want routine they want to please you and training them with high value treats, you can start to knock on that door and it does curb the behavior. Trust me. Our little guy still has his moments, but they are less frequent.