The Worlds Biggest and heaviest Bulldozer ever made is the Acco. It is a non production custom 'one-off ' that was built by the Italian Company Umberto Acco in 1980.

The Acco was constructed mainly of Caterpillar parts, many other components however were specially adapted, like the big shovel blade that's bigger than anything Caterpillar make.

The Acco has a colossal gross weight of  183 tons! and is powered by two 675 hp Caterpillar engines placed horizontally opposed, which deliver a total combined output of 1350 hp.  It can reasonably be assumed that the drive train mechanism share the power of the combined engines output, rather than being divided to drive a particular set of drive wheels.  This would be the easier and less expensive option.

This amount of shear horse power drives both the upper and lower rear mounted drive sprockets, having two drive sprockets maximizes torque, delivering fantastic pulling and pushing power. The teeth that run along the surface of the tracks are quite deep, and would greatly assist traction by in digging in soft earth and sand and providing maximum grip.

The Acco has a blade that is 23 feet wide and 9 feet high, whilst the total length of the Bulldozer is over 40 feet, from  the tip of the blade to the ripper on the rear.  As the picture below relates, the ripper alone is about 10 feet tall ! powered by huge hydraulic rams.  This is total earth manipulation at its best!

The Acco was initially built to be exported over to Libya, North Africa in the early 1980's, to help in land development, but as the President of Libya, Col Gaddafi was allegedly involved with International Terrorism at that time, the United Nations endorsed and sanctioned huge trading embargo's on that Country.  As a direct consequence of these trading restrictions the completed Acco Dozer was never shipped to its intended destination, but remained redundant in Italy where it was built.

Later with the sad death of Umberto Acco, the Directors of the company decided not to continue with many of Umberto's innovations and  along with a few other machines, the dozer of which had never been put to any operational use, was sadly put into storage where she remains today.

The above picture shows a Gent standing at the rear of the Acco to give some idea of the size of this truly enormous Bulldozer.  The twin upper and lower drive sprockets can be seen in this image too.  That is some serious metal harnessing power, and it would be great to see this Acco Dozer in action.

The future of this massive dozer is uncertain, it could become an attraction at some possible sight seers venue or it could be cut up for scrap metal value...I hope its not the latter.