The Caterpillar D11 series is a giant of a Bulldozer for the mining industry. Primarily designed as a Bulldozer, but also used for push loading scrapers, and ripping rock overburden. The D11N which was introduced in February 1986 to replace the D10. The D11N had some major improvements over the D10, it includes a bigger track and blade,a longer track by 21 inches. The U blade was just under 21 feet long and 7-7 inches high. This upped the blade capacity to 45 yards. The D11Ns weight was now 204,517 lbs. It was 770 hp powered by a 2,105 cubic inch 3508 V-8. The D11Ns improvements made it over 10 percent more productive then the D10. In 1987 an hydraulically powered impact ripper was added to the D11N which raised the weight up to 225,950 lbs. This would be come known as the D11N Impact Ripp