The Tatra 815 is a truck family, produced by Czech company Tatra. It uses the traditional tatra concept of rigid backbone tube and swinging half-axles giving independent suspension. The vehicles are available in 4x4, 6x6, 8x8, 10x8, 10x10, 12x8 and 12x12 variants. There are both air-cooled and liquid-cooled engines available with power ranging from . As a successor to Tatra 813 it was originally designed for extreme off-road conditions, while nowadays there are also variants designated for mixed (both off- and on-road) use. The gross weight is up to . The 815 and its descendant models took the Czech truck racer Karel Loprais to victory six times in the Dakar Rally. History Designed to eventually replace the Tatra 148, the prototype Tatra 157 was introduced in 1970 and several more prototypes were designed between 1970 and 1974 period but no production resulted. Due to protests from another Czechoslovak manufacturer LIAZ which was assigned by the government central planning committee to manufacture trucks of similar class, Tatra dropped the 157 and instead started to concentrate on a heavier class as the replacement for the 813 and 148 which was introduced in 1983 as the 815 series. In 1989 Tatra modernized the 815 and introduced new 815-2 which received further upgrade in 1994 and just 3 years later in 1997 the new cabin TerrN°1 is introduced. Another facelift followed in 2000 where changes included among others new instrument panel and cab attachment and for the first time there is an option for fitment of liquid-cooled engines. The latest facelift of cabin came in July 2010. Due to emission requirements changes in 2003 Tatra developed all new V8 engine T3C to comply with Euro III where it followed the tradition once again with its air cooling design. The further developed T3D engine was introduced in 2006 with its SCR and Euro IV compliance. Design While most other manufacturers derive their trucks from road applications, the 815 was purposely designed for extreme off-road conditions, and its road versions are derived from the off-road original concept. The principle consists in a central load-carrying tube with independently suspended swinging half-axles bolted as one whole. This gives Tatra vehicles outstanding driving qualities in the most difficult terrains. The concept allows higher off-road speed compared to classical rigid axle design. Central load-carrying tube The primary structural feature of Tatra trucks is the central load carrying tube, also called