I second what Bloo has said. Pits are known to be dog aggressive, but so are many other breeds. When you own a pit, you have to take that into consideration and adjust accordingly. A dog may not start out dog aggressive, but that can change.
Question is…is it really dog aggression? Dogs that have a fear towards other dogs also appear to be aggressive, when it is really just a reaction to fear. They want the dog away from them, and that is how they react. Some hide, some react by lunging and striking out. Binks may never get along with other dogs, and the key to having a dog like this is daily management and training.
One thing to do is to NEVER yell at Binks, jerk the leash, or hit him for the way he is reacting towards another dog. I am not saying that you are, just reminding you to not do it. By doing that, you are reacting in a way that may teach Binks that all dogs mean my mom is going to flip out and I need to react even more to that dog! That is the last thing that you want. You want to be as polite and calm as you can be. Dogs can sense you are tense or nervous and will also react accordingly.
Dogs that are reactive to other dogs or humans have a threshold of when it happens. Does it happen when the other dog is 100ft away, or 25ft away from you? This is one thing that you have to figure out, and start training far away and gradually work up to close encounters.
A way to start managing the issue is to reinforce that seeing a dog is a positive thing. When you notice a dog coming at you, have really high-value treats ready to give Binks. I use cooked steak, hot dog, liver, squeeze cheese, etc. It needs to be something that Binks rarely, if ever, gets. When you see Binks notice the dog, this is when you have to get to work. Don’t wait until Binks reacts. If you see the dog before Binks does, then you can start to get his attention to you. If Binks knows “sit” and “watch me”, then you can begin to work on addressing this issue by sitting Binks and making him watch you and not the dog, feeding him treats one right after another.
Once you have Binks attention, feed him treats until the dog passes. This may requre you having him sit and standing in front of him to block the view of the other dog. If you can walk on, feeding treats as you go, that is great too. Once the dog is out of view, stop giving treats and continue on as if nothing happened.
You want Binks to look to you for help/treats when another dog is approaching. Of course, it isn’t going to work 100% of the time, but over time, it will get better until you are comfortable with handling the situation.
With the situation in the car, that may be something that you need to spend some time in the car, going up and down the driveway, or even sitting in the car with the other dog reacting. Again, keep everything positive. One thing to keep in mind is that dogs tend to be protective of the car, so he may continue to bark and do what he does. Just keep windows up (dogs shouldn’t hang their heads out the window when you drive anyway) until there are no dogs in sight. Again, make it all a positive experience. I have been known to sit in cars with dogs who bark and growl at humans as they walk by, one by one feeding the dogs treats when there is a human present. Once the human leaves, the treats stop. After awhile, the dog sees a person, and the dog looks to me for treats. That is what you want. Eventaully, I phase out treats, but still give them at random so the dog never knows when he will get a treat. It keeps him looking at me. After that, the dog associates the people outside of the car with a good things-yummy pieces of steak and kielbasa!
There are many good articles on the web about controlling dog fear/agression. I suggest you do a lot of research and start working on Binks NOW before it gets out of hand. This is a hard issue to tackle, but with time, patience, and proper management, you will have a dog that won’t react as much as he used to.