I Need Advice from the Experts... I Need Mommies!!

Can you firmly (and repeatedly, of course,) let him know that he cannot go anywhere in the car unless he remains fastened in his seat? Also, if you are wearing headphones, he probably is mad that you are tuning him out. Have you tried listening to some kids' music in the car? Baby Beluga by Raffi, for example, is soothing music to my ears. Maybe try classical music, as well. Whatever you do, this will last until he understands that you WILL keep him in his carseat. Also, eventually he should get tired of being so upset. I feel for you.
Amy

ITA with the music--that helps us. Also, why don't you just focus on the carseat, since that's the important one. I don't bother with the other equipment, I just carry my kids at that stage in a baby carrier. If they're on my back in the mei tai or wrap, they can see over my shoulder, they're happy and I don't have to worry about strollers or carts.

Sounds like you've tried just about everything, so not sure if these will help or not. We had tons of problems with our daughter in the car (from birth til just past a year). She seemed to do better when she could see things -- us, herself, outside, etc. We also got her the Elmo/Cookie Monster magna doodle thing. She could draw on it and it made noise, so she was happy. We also had one of those glo-worm dolls (that light up) for when it was dark.

In stores, we just gave up the fight -- we'd let her walk whenever possible or let her sit in the basket part instead of the seat. Hope you figure out something or that this passes soon!

That sounds very frustrating! I wonder if he actually is just very sensitive to the physical feeling of being restrained. I agree with the writer who suggested focusing on the car seat only for now. Maybe he will outgrow it (meanwhile, don't plan any long car trips?)

The only thing I can think of - does he show any other signs that he might have a sensory sensitivity? (like reacting to loud noises or lights or crowds?) If it is sensitive to pressure or sound or other stimulus, it might be that adding toys/music just makes it worse as he gets overwhelmed. You could experiment with trying a nighttime drive with no lights, toys or music and see if the results are any different.