The Community star will appear in a multi-episode arc on the FX biker drama as a man who finds himself in trouble due to an ill-conceived double-cross.
Speaking in the show's latest Before the Anarchy web series, he joked: "He's probably the best character this show's ever had.
"My performance should bring this whole thing to a screeching halt."
McHale recently stated that he enjoyed working on a "straight drama" series such as Sons of Anarchy.
Sons of Anarchy kicks off its fifth season on September 11 on FX.