The size, durability, reliability, and low operating costs have made the D9 one of the most popular large track-type tractors in the world.

In 1965, West Coast businessman Buster Peterson hooked up a pair of D9Gs to pushload the largest wheel tractor scrapers built.

[i] The new undercarriage design reduced strain and shock loads on the final drives[2] and gave the "belly pan" more ground clearance.

The D9's primary working tools are the blade, affixed to the front and controlled by four hydraulic cylinders, and an optional ripper, which can be attached to the back.

The blade is mainly intended for earthmoving and bulk material handling: pushing up sand, soil, and rubble.

It also can be used to push other heavy equipment such as earthmoving scraper pans, and in military applications, main battle tanks.

Caterpillar Inc. does not manufacture a military version of the D9 per se, but the attributes that make the D9 popular for major construction projects make it desirable for military applications, as well, and with Israeli modifications and armor, it has been particularly effective for the Israel Defense Forces[3] and also used by KBR[citation needed] in Iraq.

D7G bulldozers are still very common in US combat engineering battalions, but a series of oft-recurrent suggestions have been made to replace the lighter D7Gs with the newer and more heavily armored D9s.

[citation needed] IDF D9 bulldozers were used during the Second Intifada (2000–2005) to demolish Palestinian structures and clear improvised explosive devices.

The Israeli armor provides protection from small arms and explosives, and the bulldozers were used the Battle of Jenin 2002 during Operation Defensive Shield.

A 2003 incident involving an IDF D9, in which a 23-year-old American activist was killed, resulted in a lawsuit brought against Caterpillar, Inc. in the United States.

[4] The court dismissed the case on grounds that it was outside their jurisdiction, and that Israeli tort law was a sufficient avenue to pursue remedies.