Is having about $4,000 in a checking account too much?

I have an online bank it it offers a feature which lets you tell it the maximum that should be in the account on a specific day of the month (just after pay day for instance). Then it moves anything over that automatically to my high interest account. Perhaps your bank has or could create a similar feature.

There is no need to keep any more in a current account than you intend to spend in an average month.