Since there have been developments in brakes, differentials and other aspects of the drive-train to increase speed, usability and reliability. Full suspension (meaning all three live axles now are fitted with suspension) came with the 2007 Volvo CE A35E/A40E. Volvo trucks allow each of the three solid axles to move and twist independent of the other two, and therefore calls it "independent suspension" in their marketing materials, although it still utilizes solid axles, unlike independent suspension in automobiles. Others have since followed suit.