I would keep a prong collar or dominant dog collar and long line or leash on him at all times that you're there to interact with him. This way you can issue a correction when needed. An e-collar would also be a good idea once a trainer shows you how to use it properly. You're definitely being tested to see if you're weak or strong leaders. Both Bullmastiffs and AmStaffs are noted for doing that. <img src="/ubbthreads/images/graemlins/cool.gif" alt="" />

I have never owned a bull mastiff, only German Shepherds, but from what you are saying, it sounds like the dog is wanting attention from you. If he goes into submission with out any trouble when you have his leed, then he seems to know that you are in charge. I would try to play with him more. And also spend time working with him on the skills he learned in his obedience classes. When you were doing classes with him, he got used to you working with him and spending that time with him. Dogs want to please us, and be close to us. If you don't continue to use the commands that he learned in obedience classes he will forget what he learned. Unless he starts really biting hard and not play biting I think it is an attention issue.
Good Luck!

linda's take is how i read this, too. the dog wants to play with you and wants your attention. mastiff breeds are deeply affectionate and need lots of owner attention. it sounds as if this is his idea of playing with you. how did he get that idea? maybe you played with him in this fashion when he was a little puppy?

owners of mastiff puppies have to remember not to allow them to do anything that is cute when they are pups but unmanageable when they grow up and weigh 150+ lbs!

just wanted to add: it sounds like he is already submissive and obedient, he just needs to understand that this play style is not OK. with some mastiffs, a severe NO is all you need. with others, you might need a well-timed correction with a prong collar. he sounds like he's a "soft" dog and you just need to make this behavior unrewarding for him. be consistent and give him other ways to play with you. tug of war or fetch or a good run!

I have some kind of mastiff mix that I got from the pound that used to have jumping issues. What a pain in the neck that was to eliminate. After trying everything but the prong collar (I never heard of it back then), from all positive and motivational to physical compulsion, I finally cured the problem by putting my knee up and tossing the dog on his back. Sounds extreme, and mean huh? I don't care. We tried EVERYTHING else. You must be consistent with it. He jumps, you bring your knee up say NO & SIT, dog falls on his back, you turn your back and ignore him until he learns to sit for attention. You're not kicking him, you're simply putting your knee up and toppling his balance. If visitors come over, tell them to do the same. Putting him on lead loaded my dog up even worse. With my dog it wasn't an aggression or boredom issue, the issue was he was a big dope who got so excited he didn't know how to channel it. Working the dog in drive under distractions will help a lot. At some point if you get this under control you may find that teaching the dog appropriate times for rough kind of play is acceptable but only when you say. Approach that with caution though because if you don't do it right you could make the problem worse I think.

If he jumps at your back and bites I would give him the mother of all corrections with a very loud and stern NO and the proceed to ignore him till he starts showing behaviors that you like and expect. Of course you'll have to do your part to teach them. If you feel you can conquer the problems without compulsion, go for it. My dog would only respond to physical compulsion, and I'm pretty good at the motivational psychological tactics. After trying everything with him I've found that some dogs need harder corrections. I have a female who only requires a gentle voice correction for most things. What a relief <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> Good luck <img src="/ubbthreads/images/graemlins/smile.gif" alt="" /> With consistency and hard work he'll be just fine!

I forgot the most important part, LOTS of exhuberant praise for good behaviors, but gauge his reaction to see if it's too exhuberant and makes him uncontrollable and excited again. If it does than tone down the excitement in your praise.

I will try all those ideas, thank you. I am wondering though about the trainers that Elaine had talked about. I have made some calls and am waiting to hear back but those were all male trainers. Are there any females that do the same training in the Madison, WI area? Tank has issues with males and I don't want to have him go to a trainer that will stress him out.