In December 2006 the updated testing methodology was finalized to be implemented in model year 2008 vehicles .
In December 2006 the updated testing methodology was set the precedent of a 12 - year review cycle for the test procedures .
In December 2006 the updated testing methodology was finalized to be implemented in model year 2008 vehicles and set the precedent of a 12 - year review cycle for the test procedures .