Komatsu Dozer Engine

Komatsu Dozer Engine parts list
Image	Fits Model	Description	Details	Part #	Price	Product Details
	See Details	4D102	Engine - Long Block (New)		KM-4D102-LB-N	From $4,984.00	View Info
	See Details	6D102	Long Block PLUS (New)		0	KM-6D102-LB-N	Call for Pricing	View Info

New long block engine assemblies for Komatsu dozers, covering both the 4D102 and 6D102 engine families used across a wide range of Komatsu crawler dozers. These complete long block assemblies provide a reliable foundation for engine rebuilds, reducing downtime on the job site.

Fits Models At A Glance

4D102 Engine Series: D37E, D37P, D39E, D39P
6D102 Engine Series: D51E, D51P, D61E, D61P, D65E, D65P

Key Notes

Assembly Type: Long block — includes block, head, and internal components
Condition: New assemblies, not rebuilt or remanufactured
Engine Families: 4D102 and 6D102 inline four- and six-cylinder diesel engines
Application: Designed for crawler dozer engine replacement and rebuild applications

Why Choose Broken Tractor

✅ New long blocks available for immediate purchase
✅ Covers multiple Komatsu engine families and dozer lines
✅ Fast shipping from Baton Rouge, LA and Kimbolton, OH

Frequently Asked Questions

What engine is in a Komatsu D65 dozer?

The Komatsu D65E and D65P dozers in our fitment list use the 6D102 engine family. Broken Tractor offers a new long block for the Komatsu 6D102 engine (SKU KM-6D102-LB-N) for those machines. Komatsu has built D65 dozers over many years, so confirm the engine model on your machine before ordering.

Which Komatsu dozers use the 4D102 engine?

The 4D102 inline four-cylinder diesel is used in the Komatsu D37E, D37P, D39E and D39P crawler dozers. We carry a new long block engine for the Komatsu 4D102 (SKU KM-4D102-LB-N) for engine replacement and rebuild work on these models.

Which Komatsu dozers use the 6D102 engine?

The 6D102 inline six-cylinder diesel is used in the Komatsu D51E, D51P, D61E, D61P, D65E and D65P crawler dozers. Broken Tractor offers a new long block for the Komatsu 6D102 engine (SKU KM-6D102-LB-N) for these machines.

What comes with a Komatsu dozer engine long block?

Our Komatsu 4D102 and 6D102 long blocks include the engine block, cylinder head and internal components. They are new assemblies, not rebuilt or remanufactured units. Parts outside the long block assembly are not included, so plan to reuse your existing components or source them separately.

How do I know if my Komatsu bulldozer needs a 4D102 or 6D102 long block?

Check the engine model on your dozer. The 4D102 is a four-cylinder engine and the 6D102 is a six-cylinder engine. In our fitment list, the D37 and D39 models use the 4D102, and the D51, D61 and D65 models use the 6D102. If you are unsure which engine your machine has, call (800) 909-7060 and our parts team can help confirm the right long block.