The bolt on mine was frozen tight. I tried using a 3/4" drive 600 ft lb air impact gun to remove the bolt, and it would not budge it. I was concerned about damaging the crank also, since the bolt was so tight. Call me a caveman, but I used a chain type pipe wrench wrapped around the harmonic balancer (where the serpentine belt rides) and a 4' cheater bar, and it worked like a charm