Need help!!!!!

I need help. My sister n law left her dog with us several years ago, it was a rescue dog, pit bull/lab mix. We now have the dog and are doing the best we can. When Tucker (dog) was younger we could manage him, we had him on an electric color/underground fence, and he did fine. Then he started running out of the fence and started biting the neighbors and anyone that came to the house that he didn't know. Then he started snipping at me and the kids when we tried to get him to do things like go inside and he wouldn't wont to go. We can NO longer leave him unattended, I refuse to deal with him alone, my husband is the only one that can handle him. Due to the biting issue, we have started to either leave him in our basement (where the rec room is too) or only choice outside on a chain (hate it). We don't no what to do. We tried several years ago with training and did didn't seem to do very well as you just don't know what will set him off and make him bit. He can be the sweetest baby, so loving and kind but then there is other times like last night when I gave him a new bone and he had walked away, my husband went to pick it up Tucker(dog) went full force over to my husband and bit him twice on the arm and brought blood. After he bit my husband, I think he realized what he did and no longer wanted the bone. I don't know what to do. Now, its getting hot outside we are leaving him inside more and he has tore up my back door, I have attached pics to show the damage. I feel terrible that we have to leave him chained up all the time but when he is inside he wants out. He does not get the exercise that he needs due to the fact we cant trust him off the leash and even on the leash he is wild. I just don't know what to do. We have had several dogs and we have never encountered anything like this before. What do we do???? The biting is a problem, I cant trust him, and I hate that we have to leave him chained up all the time. What do we do??? Need help!

One thing struck me straight away, you don't seem to have ever bothered to do any training with him. He's been left to do as he pleases and therefore knows no boundaries, nor what behaviours are expected of him and the difference between right and wrong. Therefore you are in the situation you are in now. Have you considered doing some proper training with him so he knows the basics and what is expected of him, you are going downhill very fast now with him as he is making it up as he goes along as no one has given him any information otherwise. Using electronic devices is not a long term answer, its a short term answer to a long term problem, that is never going to work

We have done training with him. He was wild when we got him. He would jump on you, run from us, get into things, chew up everything in site, so we took him to a training facility. We went through two months of training and he did calm down. The biting issue and the running out of the fence came about a year or two later, and it really came out of nowhere. We don't know if its because he is trying to be protective because he feels like everyone abandons him or what?? But we cant trust him. We are consistently trying to work with him but you cant trust him, he is to unpredictable. Or for instance when he chews up our back door to get, he doesn't do it when we are there he does it when we are gone, we of course try to correct him.

2 months???Is that it??? You have only just touched the surface, yes he did improve, then you stopped the training and he went backwards. Training is every single day, 20 minutes tops, then a training class once a week with someone who knows what they are doing, has walked the walk.
Think about it, you have children, would you send them to school for 2 months and expect them to attain a college degree.
My 13 month old puppy has had more training than your dog.

Yes, two months. that is why I am asking for help on what to do. I have had and have another dog now that doesn't act this way and is completely trained, well trained actually. I have never experienced a dog with behavioral issues like this one. We don't know what we are doing. Will more training keep him from biting? Make him trustworthy? My other dogs never acted this way. This dog is way beyond our scope of raising dogs and need advice, not criticism. Most people would have gave up on him already. At least we are trying.

I'm not criticising, what I am doing is pointing out what the underlying problem is. Sooooo find a training class with an experienced instructor who can help with the issues. Every day do a few minutes training, even if its only getting him to sit on command, then reward him. Once you've got sit, then work on down, then work on stand. Once he's got those in his vocabularly, then you can work on Leave, which given the circumstances you need to have spot on. Teach leave by putting a treat in your hand, as he goes to take it, close your hand and say Leave, eventually he will back off when he hears leave, when he does that, reward him with the treat. This will be spread over a good while by the way, don't move onto something new till he is good with what you have taught him so far. Don't let him snatch anything either. He needs to understand who is in charge here, and it is not him anymore. Be firm but kind, a sharp NO when he moves off your chosen agenda. Do not do more than a few minutes training, he will learn to associate the time you spend with getting treats. Make sure you take him to training classes on a regular basis and practice what you have learned every day. It is a long hard road back, but it is doable, patience and persistence are needed, and you'll need a lot of both.

We do work with him, he will sit when I tell him to sit, lay stay, etc. until he sees something he wants to go after and then its like all the training goes out the window, all of our commands he ignores. His favorite thing to play is finding things, so like yesterday, when I bought him the new bone we were playing with him and when my husband went to take it he bite him in two spots. He just got upset and snapped. You could tell he knew he had done something wrong after he bite my husband but I just cant figure out what made him snap on my husband. Its that kind of behavior that worries me.

Because he has no understanding of the fact that if you want something off him he has to give it up with no fuss. Hence my point about the Leave command. You need to get him on a line and do the training every day,so it becomes automatic to him.He is used to having his own way and doing what he wants, and so far its worked for him, so why stop.
If he's on a line then he can't decide he's seen something more interesting, it is up to you to make him interested in what you have to offer.

I would absolutely not at this point take anything from this dog. Give him something and leave him alone with it. He is resource guarding and he's learned to react fast and hard.

Honestly, this dog seems to have a mess of issues, mostly fear-related. He resource guards because he's afraid you're going to take his food away. I can't recommend Jean Donaldson's book, Mine! A Practical Guide to Resource Guarding in Dogs enough. Great stuff there on how to deal with a resource guarding dog. But first and foremost is NOT reinforcing the dog's fear by actually taking away a prized possession.

He also seems to have some sort of separation anxiety, hence the destruction when you're out.

And some of this may very well stem from the shock collar he had to deal with. Those underground fences are a menace and can make an already anxious dog even more of a mess. The fact that he's busting through it is a bad sign. At this point I might consider just going outside with him on a long line and playing with him. I wouldn't chain him (that can lead to serious frustration -- the dogs that bite the MOST are chained dogs). I would be out there WITH him when he's outside and interacting with him. He sounds like he needs far more stimulation than he's getting.

I agree wholeheartedly that you need to get with a trainer now. Perhaps YESTERDAY. I might even suggest finding a behaviorist or a veterinary behaviorist. This dog seems to have some serious fear and anxiety issues and you need a real plan that you can stick to. And he might even benefit from some sort of anti anxiety medication (possibly...not seeing the dog myself it's hard to tell but a vet behaviorist would be able to tell if there's any medication that could help).