The number of bolts securing the sensing ring to the crankshaft has been reduced from four to three on 4B1-equipped 2008-2011 Outlander, Lancer, Lancer Sportback, Lancer Evolution and 2011 Outlander Sport.

This change took place beginning Oct. 4, 2011, with engine serial # GR1742.

The bolt hole was eliminated in the crankshaft, but not in the sensing ring.