Billet Lower crankshaft gears / sprockets for all 2007-2014 GT500 The factory powdered metal crankshaft gear has proven to be a weak link, failure of this gear results in severe damage to the valvetrain and cylinder heads. Protect your investment with this Heat Treated Billet steel gear from MMR. Direct replacement. As used by NMRA Coyote Modified and NMRA renegade record holders and the World Record Holder and first in the 6's!Learn More