I would start with a "Nothing in Life is Free" program. Basically everything he wants in life, he earns with good behavior. So he wants his dinner, "sit" if he listens he gets his bowl, if he doesn't you set the bowl back on the counter and he can wait 5-10 minutes before getting another chance. Even better, have him earn his food kibble by kibble (or handful by handful if you're in a hurry). He wants attention he has to sit first or he's ignored, he wants to go for a walk means a couple tricks first, he wants to go outside/car ride/have a cookie/ get on the couch/ come in the house etc he does something first. There is no punishment for not listening except he doesn't get what he wants.
I've used this for both pushy dominant dogs and scared insecure dogs and it can really make a difference.
I would also stop letting him sleep anywhere except his dog bed, and when you want to give him attention call him to you. You want to avoid putting him in a situation where he will growl until he learns better manners.
Teach him "go to your bed" and make it fun. My dogs will run and leap on their beds. Send him to his bed as needed or for time outs. Sit on his bed and call him to you, make it fun. My dogs get sent to their beds for rowdy or out of control behaviors or for misbehaving in general. They get a 1 minute time out and then are calmly released from it (no praise). If they can't calm down enough to go to their beds then they get a time out either tied to a door handle or in a crate (the worst punishment possible for my one dog, who loves her crate otherwise). In other words make his sleeping spot under your control.
The dog to dog interactions, I can't really help with. My male pit mix is that way too. He'd just rather not have rude dogs up in his face. So we don't go places that will happen.
I've used this for both pushy dominant dogs and scared insecure dogs and it can really make a difference.
I would also stop letting him sleep anywhere except his dog bed, and when you want to give him attention call him to you. You want to avoid putting him in a situation where he will growl until he learns better manners.
Teach him "go to your bed" and make it fun. My dogs will run and leap on their beds. Send him to his bed as needed or for time outs. Sit on his bed and call him to you, make it fun. My dogs get sent to their beds for rowdy or out of control behaviors or for misbehaving in general. They get a 1 minute time out and then are calmly released from it (no praise). If they can't calm down enough to go to their beds then they get a time out either tied to a door handle or in a crate (the worst punishment possible for my one dog, who loves her crate otherwise). In other words make his sleeping spot under your control.
The dog to dog interactions, I can't really help with. My male pit mix is that way too. He'd just rather not have rude dogs up in his face. So we don't go places that will happen.