This model year became even more smooth. Chevy clipped off the pointy edges and dented in the upper portion of the grille. The tail lights were no longer surrounded by an aluminum strip, but rather trapped in a body color, while the aluminum was bumped above the lights in an upside-down "U" shape spanning the entire rear. Chevy also released refined transmissions this year, making a quieter 3-speed synchro-mesh, and putting an aluminum housing on an all-helical 4-speed synchro-mesh. This was the year that the Chevelle was introduced to the world, showing a shift in importance of the muscle car.