These machines are tracked vehicles used to assemble remote drill sites and drill rigs working in South America. They are designed to operate in very extreme conditions throughout the globe. All-Track vehicles are in use from the Arctic to the Amazon. They are equipped with John Deere diesel engines and Funk Pump drives.
In these photos, they are being used on site to assemble various components for a 1500 hp heli-portable drill rig. In the one photo, they are trying to free a stuck bulldozer from a mud hole. The vehicles in the pictures are All-Track AT-80HD equipped with a large knuckle boom crane.

For more information on All-Track and their all terrain carriers, see the PowerSource article Trek the Tough Terrain.