Is the 4th recommendation letter too much?

Dartmouth requests 3 recommendations (one of them is a peer rec) but on CommonApp, one can submit 4. I have 4 good recommendations… my question is should I submit them all or would the admissions officers be irritated by the extra letter?
I’ve seen in some places that officers don’t like to see materials that weren’t asked for and in others that the extra recommendation can’t hurt - what do you think.