The big daddy of CAT bull dozers is the D11, a truly impressive machine. Norscot makes a couple of different D11's of which mine I think is the oldest. The newer ones all got real metal tracks, mine got plastic, which looks really nice. You even get it in silver finish.
The Caterpillar D11 is a large bulldozer, manufactured by Caterpillar Inc. in East Peoria, Illinois, and mainly used in the mining industry. Primarily designed as a bulldozer, it also used for push-loading scrapers, and ripping rock overburden.
The D11R and D11R Carrydozer were introduced at the Las Vegas, Nevada at MINExpo International 1996. Both were 770 hp (570 kW) and that would be increased to 850 hp (630 kW) later in 1997. Other improvements made to the D11R were Fingertip Controls and Electronic Clutch and Brakes. The Finger Tip Controls (FTC) allowed the D11R to be steered with a single lever (joystick) on the left hand side. The D11R now weighed 230,935 lb (104,750 kg). The Carrydozer version has a special blade with a curvature that allowed 57 yards (52 m) to be pushed. The "Carrydozer" had the structure strengthened considerably for the extra weight and much bigger blade that it carried up front. Both D11Rs received a new Caterpillar 3508B EUI diesel engine with electronic controls at 915 gross hp. The Carrydozer versions weight is just over 120 tons at 248,600 pounds.According to Caterpillar by the year 2000 over 3,000 D11s had been produced at their plant in East Peoria.