Caterpillar D8
# Caterpillar D8

The Caterpillar D8 is a medium track-type tractor designed and manufactured by Caterpillar. Though it comes in many configurations, it is usually sold as a bulldozer equipped with a detachable large blade and a rear ripper attachment.

## History

* 1935: RD8 (132 hp [98 kW]) introduced.
* 1937: The "R" prefix dropped, D8 debuts.
* 1940s: D8 2U Series (148 hp [110 kW]) introduced
* 1950: D8 new front-rounded grill that would last until D8K was replaced by D8L in 1982.
* 1955: 1H Series D8 ends production; 191 hp (142 kW) D8E and D8D introduced with new 1,246-cubic-inch (20,420 cc) displacement (CID) D342 diesel engine. D8D had a torque converter and D8E had a direct drive transmission.
* 1956: D8D replaced by D8G.
* 1956: D8E replaced by D8F.
* 1958: 235 hp (175 kW) D8H introduced.
* 1965: Power increased to 270 hp (200 kW)
* 1970: D8 46a 48a power increased 280 hp (210 kW)
* 1974: 300 hp (220 kW) D8K replaced the D8H.
* 1982: 335 hp (250 kW) D8L replaced D8K. The D8L was the first D8 with the elevated drive sprocket undercarriage.
* 1984: D8L SA (special application) for farming applications premiers. Available with a three point hitch, for mounted implements.
* 1987: D8N (285 hp [213 kW]) with differential steer transmission, the first track-type Caterpillar tractor to have one.
* 1996: 305 hp (227 kW) D8R replaced D8N.
* 2000: D8R Series 2 replaced the D8R.
* 2004: 310 hp (230 kW) D8T ACERT replaced D8R Series 2.

## Blades

Several types of bulldozer blade can be used on the front of the tractor:

* Straight ("S-Blade"): A short blade with no lateral curve and no side wings. It can be used for fine grading
* Angle: held by a U shape frame that has three holes on each side, to set the blade to 3 positions: right, center, and left.
* Universal ("U-Blade"): A tall and very curved blade with large side wings to carry more material
* "S-U" combination: A shorter blade with less curvature and smaller side wings

Other blade types include landfill U-Blades, woodchip U-blades, and two-way blades for work inside the holds of ships.

