John Deere PowerTech™6068 Series Industrial Diesel Engines encompasses a range of internal combustion engines. This 6 cylinders , 6.8 L engines series  have an unparalleled track record for providing hard-working, reliable, and efficient engines that don’t let you down, even in the most extreme conditions. Whatever you throw at them – vibration, extreme temperatures, dust – John Deere engines keep working day after day. The 6068Engines series include the diesel engines: 6068HF158,6068HF158R,6068HF258,6068HF258R,6068HFG20,6068HFG55