What Am I?

Clue 1:  I am a special type of tractor.

Clue 2: I am very big and tough. I am built for hard work.

Clue 3: I am used to help clear the way to build new buildings.

Clue 4: I have caterpillar tracks instead of wheels.

Clue 5: I can push very big piles of dirt and rocks out of the way.

Clue 6: I have a big blade on the front of me called a dozer blade.