Originally Posted by Matt Finley
Ok. But I’m not aware of any other sus chords besides 7, 9, and 13. Maybe there’s some more music theory I don’t know?
I'm not particularly advanced in my music theory so I can't really comment there, however going from our official chord list there are quite a few suspended 4 chords:

Code
Csus, C7sus, C9sus, C13sus, C7susb13, C7sus#11, C13sus#11, C7sus#11b13, C9susb13, C9sus#11, C9sus#11b13, 
C7susb9, C13susb9, C7susb9b13, C7susb9#11, C13susb9#11, C7susb9#11b13, C7sus#9, C13sus#9, C7sus#9b13, 
C13sus#9#11, C7sus#9#11b13, C7susb5, C13susb5, C7susb5b13, C9susb5, C9susb5b13, C7susb5b9, C13susb5b9, 
C7susb5b9b13, C7susb5#9, C13susb5#9, C7susb5#9b13, C7sus#5, C13sus#5, C7sus#5#11, C13sus#5#11, C9sus#5, 
C9sus#5#11, C7sus#5b9, C13sus#5b9, C7sus#5b9#11, C13sus#5b9#11, C7sus#5#9, C13sus#5#9#11, C7sus#5#9#11


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