Jeep Wrangler driving off-road with a 4BT Cummins engine
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Who we are

Big Bear Engine Company - Experience The Power of Diesel

Big Bear Engine Company was originally founded as a division of a larger diesel engine remanufacturing company in Denver, Colorado. As the company grew the demand for smaller industrial Caterpillar and Cummins crate diesel engines became apparent and Big Bear Engine Company spun off on its own. Today the two companies still work side by side and are located in the same engine manufacturing complex in Parker, Colorado.

Big Bear Engine Company

Today we specialize in engine 3 models: Cummins 4BT Engine, Cummins 6BT Engine and the Caterpillar 3306 Engines. Our talents lie within the finite science of engineering and manufacturing of diesel engines. Big or small we’ve done them all! All of our engines are produced using brand new parts and are assembled to exact OEM tolerances.

In addition to component built long blocks and extended long blocks engines we also have the capabilities to remanufacture diesel engines. We can reman cylinder heads, camshafts, crankshafts, blocks, rocker assemblies. Surfacing, grinding, line boring, welding and magnafluxing are in our blood!

We believe in putting our customers first and want everyone to have a pleasant buying experience. That means if there is any problem we aim to “make things right” at the end of the day. Whether you are installing at 4BT in a Jeep or a Skid Steer we are here to make sure you get the most of your engine.

Big Bear Engine Company Crew

The Reman Crew

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Component Build Diesel Engines:

Cummins 4BT, Cummins 6BT and Caterpillar 3306 Engines Models. Our prices and warranty can't be beat!
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Remanufactured & Used Engines:

We have the abilities to remanufactured all of the hard internal parts of the engines from the cylinder heads to the oil pan. In addition to reman engines we also are a leading supplier of used cummins 4bt engines, 6bt engines and caterpillar 3306 engines.
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Cummins and Caterpillar Aftermarket Parts:

Inframe and Overhaul Kits, Water Pumps, Oil Pumps, Gaskets, Bearings, Turbos, Injectors Aftercoolers and More.
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