The　wet　multi-disc　clutches　are　extensively　used　in　various　transmission　systems,with　one　of　the　most　prevalent　failure　modes　being　the　buckling　deformation　of　friction　components.An　improved　Hilbert-Huang　transform　method(IHHT)is　proposed　to　address　the　limitations　of　tradi-tional　time-domain　vibration　analyses,such　as　low　accuracy　and　mode　mixing.This　paper　first　clas-sifies　the　buckling　degree　of　the　friction　components.Next,wavelet　packet　transform(WPT)is　applied　to　the　vibration　signals　of　different　buckling　plates　to　partition　them　into　distinct　fre-quency　bands.Then,the　instantaneous　features　are　extracted　by　empirical　mode　decomposition(EMD)and　Hilbert　transform(HT)to　discarding　extraneous　intrinsic　mode　function(IMF)com-ponents.Comparative　analyses　of　Hilbert　spectral　entropy　and　time-domain　features　confirm　the　enhanced　precision　of　IHHT　under　specific　classifiers,which　is　better　than　traditional　methods.