About the Komatsu D155
The Komatsu D155 is a very large crawler bulldozer in the 38–41-tonne class, continuously developed since 1995. It delivers 354 hp from a Komatsu SAA6D140E-7 engine, and in its semi-U blade configuration moves up to 9.7 m³ of material per pass. The D155AX-8 variant adds Komatsu's intelligent Machine Control (iMC) semi-autonomous grading technology, which can automatically control blade lift and tilt to maintain a pre-set design grade. It is one of the most capable production dozers available for European infrastructure contractors.
Typical applications
The D155 is typically deployed on the largest earthmoving contracts in Europe — motorway interchange construction, major embankment formation, large-scale quarry stripping, and dam or flood-defence core material placement. In Germany, it is seen on Autobahn A-class projects where mass earthmoving targets run into millions of cubic metres. Some Belgian and Dutch port expansion projects use it for sand and clay placement on new industrial estates. Its size generally requires low-loader transport, so mobilisation costs must be factored into project economics.
What to look for when buying used
At 39,500 kg this machine places extreme demands on its undercarriage. A full undercarriage replacement can cost €35,000–€55,000 depending on specification — always obtain an independent undercarriage measurement report from a Komatsu dealer before purchase. Inspect the main frame for any field welding that may indicate prior cracking from hard impact work. The torque converter and power-shift transmission are complex and expensive: check for smooth shifts through all ranges under load and review any transmission fault codes in the ECM history.
Market context
At this size class, the D155 competes primarily with the Caterpillar D8T. Both are long-established platforms with global parts support. German contractor-grade D155 machines from the 2015–2022 period command premium prices due to their maintained condition, but supply is thin. Buyers across the DACH region typically source machines directly from contractor dispersal sales. Prices have been broadly stable in 2025, with iMC-equipped machines attracting a 15–20% premium over conventional variants.
Common problems at high hours
At 39,500 kg operating weight, undercarriage wear dominates maintenance costs. Track link bushings in abrasive soils require turning at 4,000–5,000 hours — full undercarriage replacement runs €35,000–€55,000. The power-shift transmission develops clutch pack slippage above 12,000 hours, identifiable by delayed gear engagement and rising transmission oil temperature; rebuild costs €18,000–€25,000. The SAA6D140E-7 engine's injector cups can crack at high hours, allowing coolant into the combustion chamber — a €5,000–€7,000 repair if caught early, but catastrophic if ignored. According to independent service workshops across the DACH region, the blade lift cylinder rod chrome plating deteriorates in quarry dust environments, leading to seal failures every 2,500–3,500 hours.
Resale value trajectory
The D155 holds value exceptionally well in the European market due to limited supply and strong demand from major infrastructure contractors. Machines from the 2016–2020 production window have retained approximately 58–65% of their original list price after five years of service, among the highest retention rates in the bulldozer segment. iMC-equipped D155AX-8 models command a consistent 15–20% premium, as contractors increasingly require machine control capability for grading tenders. The thin supply of well-maintained European machines — most are German or Swiss contractor-owned — creates a seller's market. Export demand to North Africa and the Middle East provides a price floor for older units.
Alternatives in this class
The Caterpillar D8T is the only direct competitor in the 38–40-tonne class in Europe. Cat's stronger dealer network and wider parts availability make the D8T the safer choice for buyers without an established Komatsu service relationship. However, the D155's iMC machine control system is more advanced than Cat's equivalent GRADE offering, giving Komatsu an edge on precision grading contracts. Buyers who can accept a smaller machine should consider the Komatsu D85EX or Liebherr PR744, both of which cost 35–50% less to acquire and operate while covering a wide range of earthmoving tasks. There is no viable Liebherr or John Deere competitor at this weight class in Europe.