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4BT and 6BT Engines

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Off-Roading Applications

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Available Models

CUMMINS 4BT

CUMMINS 4BT

We have new Cummins 4BT Engines in Stock from 105 hp - 140 hp with 3 different models available. Perfect for a 4BT Jeep Swap or Industrial Application.

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CUMMINS 5.9 / 6BT

CUMMINS 5.9 / 6BT

The Cummins 6BT (5.9 L) was one of the most popular medium duty diesel engines ever produced. We offer 16 models of the 6BT from 215 hp - 300 hp including marine applications

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CAT 3306

CAT 3306

The Caterpillar 3306 is a very reliable workhorse in the CAT Lineup of Engines. We offer a universal higher horsepower piston configured engine rated at 330 hp

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High Performance Diesel Engines

Look no further for all of your small heavy duty diesel engine needs. We here at Big Bear Engine Company specialize in Cummins 4BT, Cummins 6BT and Caterpillar 3306 Drop-In Engines. Our high performance diesel engines are manufactured with all brand new parts and produced to the specific OEM serial numbers to match your application. Cummins 4BT Engines in particular are perfect for 4BT Jeep Swaps as well as Industrial Applications.

• Drop In Cummins 4BT, 6BT and CAT 3306 Engines Available
• Complete and Longblock Options
• Used & Remanufactured Engines Also Available
• Get Back to Work Quickly – Ships Anywhere in the World
• 1 Year Unlimited Miles Warranty
• Save On Average 57% Over Dealers
• 4BT Jeep Swap Friendly
• Industrial Rated: Skid Steers, Dozers, Loaders, Wood Chippers, Forklifts

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Remanufactured & Used Engines

When a complete drop in option isn’t ideal we also offer many used Cummins 4BT engines as well as remanufactured engines. We are an experience source for used Cummins 4bt and Cummins 6bt engines which are all low miles, run tested and have been inspected for major wear. Our parent company remanufactures everything to OEM spec using brand new parts here at our facility in Denver, Colorado. We are primarily a full service machine shop and engine rebuilding facility with 18 machinists and master engine builders. Remanufactured Cummins 4BT Engines all come with a 1 year warranty and are inspected with using a rigorous 11 point QA procedure before they ever leave our facility.

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Overhaul Kits and New Parts

We are a one stop shop for all the parts you need for your Cummins 4BT, 6BT and CAT 3306 engines. Whether you are looking for a water pump or a full overhaul kit for your engine; we got you covered. Call us today for turbos, injectors, water pumps, oil pumps, aftercoolers, camshafts, crankshafts, cylinder heads, crankshafts, bearings, pistons, inframe kits and overhaul kits. Cummins 4BT Rebuild Kits can ship the same day as order.

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4BT Jeep Swaps

A popular application for Cummins 4BT Engines is in the use of off-road vehicles. 4BT Jeep Swaps are more than an engine option but a way of life for many enthusiasts. Cummins 4BT Engines are used in Jeep Wranglers, Jeep Grand Cherokees, Land Rovers, Toyota 4Runners, Toyota Land Cruisers, Nissan Xterras, Mercedes-Benz G500s, Ford F150s, Ford Raptors, Dodge Ram 2500s, and Chevy Colorado’s. 4BT engines are swapped in due to the increased horsepower and rugged torque ratios.

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Industrial Applications

The Cummins 4BT Engine and the bigger Cummins 6BT Engine are found in many small industrial applications. They are a popular engine choice for their durability, ease of use and reliability to get the job done. We understand the industrial off-road market… every day you are down you are losing money. Our diesel engines can be shipped the same day of order. If you have a dozer, skid steer, forklift, boom lift, wood chipper, baggage cart, loaders, street sweepers, step van, tour bus, RV or small marine application the Cummins 4BT, 6BT or the CAT 3306 engine is perfect to get back to work again.

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Shipping

Shipping

We have the logistical capabilities to ship anywhere in the world. Both engines and parts can be shipped the same day of order.

Financing

Financing

We provide financing plans for our customers who prefer a long-term payment option. The approval process is quick, hassle free and does not require any upfront capital. Conserve your working capital and get back on the road quickly.

Popular Off-Road Trails

Popular Off-Road Trails

We here at Big Bear, love off-roading as much as you do. Click here to read about some of our most favorite off-road and 4x4 trails in Colorado.

Install Partners

Install Partners

Awesome! Now that you’ve purchased that Cummins 4BT or 6BT Engine check out one of our partners to help you install the engine.

Product Gallery

Cummins 4BT Engines

Cummins 4BT Engines

4BT Extended Longblock (Bosch Injectors)

4BT Extended Longblock (Bosch Injectors)

4BTAA Extended Long Block (Rotary)

4BTAA Extended Long Block (Rotary)

Cummins 6BT Extended Longblock

Cummins 6BT Extended Longblock

Caterpillar 3306 Complete Engine

Caterpillar 3306 Complete Engine

Cummins 4BT Dozer Application

Cummins 4BT Dozer Application

Cummins 4BT Jeep Swap Engine

Cummins 4BT Jeep Swap Engine

Cummins 4BT Skid Steer Engine

Cummins 4BT Skid Steer Engine

About

HIGH PERFORMANCE DIESEL ENGINES

Big Bear Engine Company has deep roots in the heavy duty diesel industry most notably in the remanufacturing and machining of large diesel engines.

Our master engine builders all have 30+ years of building and working on diesel engines and have built engines for both the CAT and Cummins Dealers. Big or small we worked on them all! Today we specialize in three medium duty engine models: Cummins 4BT, Cummins 6BT and Caterpillar 3306.

  • Caterpillar
  • Cummins
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Address:  Big Bear Engine Company, 665 E 70th Ave, #2B Denver, Colorado 80229

Phone Number: 720-920-9162;
Toll Free: 844-340-4114

Email:  sales@4btengines.com