The bank won't do it. When you got the loan jointly, you both became responsible for the loan jointly or severally so they won't give up the right to collect the whole amount due from each party. This is why they like joint loans, if one fails to pay, they can collect the whole amount due from the other. I know you are current in your payments, but they look at the actual contract and won't release a party from half the debt (which is what you are asking in a way). In order to change the contract, you would have to refinance, and that doesn't sound like it would help your current situation.
It also sounds like you have taken precautions by having a separate account and having the payment drafted from that account. Does his employer do direct deposit? If so, can you have him get his employer to split his paycheck into separate deposits? My daughter does this, she has her paycheck split so that $X goes into her main account and $Y into another account automatically each pay period directly from the employer. It might help your situation so that you don't have to rely on him making the physical deposit.
If he won't have the employer do it, then does his bank have the ability to do auto payments "person to person"? My bank does, maybe his does as well.
What it really sounds like is your husband does not have this particular installment loan payment very high on his list of priorities. If he did, he would have the payment in your account on time.
