ADP is horrible, but their website can't change financial details (it only shows paystubs and tax forms). You can kinda change things through ADP FlexDirect, but all direct deposit enrollment is done elsewhere.

The ADP employee site hasn't changed in the past ten years and still uses basic auth. It's horrible. And freaky. When you login to your new company account, it shows all paystubs from your past employers too. [With the implication of your current payroll department being able to see how much you were getting paid at all your previous jobs since it's the same account?]