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Replacement Cummins 6CT Engines for Sale

Replacement Cummins 6CT Engines For Sale

These hard working engines go by a number of different names, but whether you call it the Cummins 6CT, 8.3 L Cummins, or later version electronic Cummins ISC, you’re looking for the same thing: a powerful workhorse that is extremely versatile for a variety of applications. Whether you need an 8.3 liter 6CT Engine to power a bus, an excavator, a crane, or something else entirely, these 8.3 L engines are a well-built option with a durable reputation.

At Big Bear Engine Company, we’re proud to offer two different replacement options for your Cummins 6CT 8.3 L Engine needs: Standard Long Blocks and more complete Extended Long Blocks.

Our 6CT 8.3 L Component Build Program:
6CT 215hp

  • 8.3 L Component Build Assemblies
  • Built with OEM and Aftermarket Parts
  • Extended Long Block Options: 215 HP, 240 HP, 260 HP, 300 HP Options
  • Standard Long Blocks (1/2 - 3/4 Assembly Engine)
  • Standard 12-months parts replacement warranty
  • 1- or 2-Year Parts/Labor Extended Warranties Available
  • Extended Long Blocks are Run tested before shipping
  • No core charge
  • Same day shipping
  • Financing available

Cummins 6CT Long Block Engine

If you have recently replaced or have well working parts from an existing Cummins 6CT engine and don’t want to spend the money on a completely new assembly, then our Standard Long Block option is ideal for your situation. Our Standard Long Block will replace the worn-out internal parts of the engine (such as the cylinder head, crankshaft, and connecting rods, among other things), without buying parts that you don’t need. You’ll be left with a high-quality solution that was extremely cost-effective to boot.

As a guide, a standard long block assembly is about 50%-75% a complete build. Think of the "guts of the engine" but nothing dressing it out.

6C Long Block Castings Includes:6CT 215hp

  • Cylinder Block
  • Cylinder Head
  • Camshaft
  • Camshaft Gear
  • Followers/Lifters
  • Pistons
  • Gaskets and Bearings
  • Rings
  • Bearings
  • Plugs and Bolts
  • Push Rods
  • Connecting Rods
  • Front Cover
  • Timed Front Gear Train Group
  • Crankshaft
  • Oil Pump
  • Oil Cooler
  • Freeze Plugs and Block Plugs
  • Front Rear and Main Seal
  • Valve Cover
  • Oil pickup tube
  • Front Sump Oil Pan
  • 1 or 2 Thermostat Block Applications
  • Outright Pricing (No Core Charge)
  • Long Block Does not include Fuel Lines, Fuel Pump, Turbo, Injectors
  • Standard 12 Months Parts Replacement Warranty
  • 1 or 2 Year Parts/Labor Extended Warranties Available

6CT Extended Long Blocks

For those who are looking for an alternative to their current engine, or want something new, our 6CT complete engines are a perfect answer.

The Extended Long Block option comes with the complete fuel system, turbo, and manifolds installed, nearly everything you need to re-power your rig. When you select an Extended Long Block, you can trust that all of the parts are brand new and have been tested for quality so there is virtually no risk of failure; plus, all of our Extended Long Blocks are test run prior to shipping to ensure it’s ready to use.

As a guide a component build 6CT assembly is about 90% brand new OEM parts 10% aftermarket when available. These are units are perfect for a customer looking to replace an existing 6CT assembly but also needs a new turbo or oil pump etc...  In most cases, an extended long block is about 75% built out and is best used in conjunction with an existing 6CT 8.3 L unit.

Extended Long Blocks Include:

  • AERA Association MemberEngine Block
  • Cylinder Head
  • Camshaft and Lifters
  • Connecting Rods
  • Pistons and Rings
  • Gaskets and Bearings
  • Plugs and Bolts
  • Push Rods
  • Rocker Assemblies
  • Injectors
  • Inline Fuel Pump
  • Connecting Rods
  • Crankshaft
  • Turbocharger
  • Aftercooler (215, 240 HP is Jackwater Aftercooled ‘JWAC’, 260, 300 HP Air to Air Cooled Setup)
  • Vibration Damper
  • Water Pump
  • Oil Pump
  • Oil Cooler
  • Accessory Drive Pully
  • Air Cross Over Tube
  • Accessory Drives
  • Inlet and Outlet Connection
  • Throttle Leaver
  • Oil Pan and Pickup Tube
  • 1 or 2 Thermostat and Block Applications
  • No Core Charge
  • Comes with 12 Months Parts Replacement Warranty
  • 1 or 2 Year Parts/Labor Extended Warranty Available


Note: Extended Long Block Does Not Include Starter, Alternator, Flywheel, Ring Gear, Flywheel Housing, Radiator, Hoses or Additional Air Cross Over Tubes, Throttle Linkage, Air Charge Cooler (260, 300 HP) , Thermostat housing, Water Outlet Connection, Fan Support, Alternator Mount, Belt Tensioner and Bracket, Air Compressor, Shut Down Solenoid


  • 6CTA – 215 HP Industrial Rating built to CPL 722
  • 6CTA – 240 HP Automotive or Industrial “Non-Road” Rating, Built to CPL 8765
  • 6CTAA – 260 HP Automotive Rating built to CPL 303
  • 6CTAA – 300 HP Automotive Rating built to CPL 333

Note: Cummins 6CT assemblies are versatile in their governed rated application meaning an automotive spec can be used in an industrial application and vice versa. We have seen all assemblies used and swapped in a variety of applications. We will work with you to determine the best fit based on your application but ultimately it is up to you to determine best use of the assembly to meet your needs.

Cummins 6CT Engine Applications

Cummins first began producing these engines in the late 1990's; there’s a reason they are still so popular today. As you might imagine, there is a wide range of industrial and automotive applications for Cummins 6CT Engines, but these are some of the most popular.

  • Construction — The fuel efficiency and compact size of Cummins 6CT engines make them a cost-effective and low-maintenance solution for construction applications. The replaceable cylinder liner block design contributes to long-lasting power, and the cold start capabilities also make these engines desirable for construction crews who need to work regardless of the conditions.
  • Buses — Many of the same factors that make Cummins 6CT engines appealing for construction also make them ideal for busses of all sorts. Because buses are responsible for transporting so many passengers, it’s crucial that they use a reliable engine.
  • Trucks — Cummins 6CT and later version electronic ISC engines are popular for medium-duty trucks of all sorts as they are powerful enough to complete a fair amount of hauling and reliable enough to get the job done without incident.
  • Industrial - The 6CT has been used in a multitude of applications from material handling, forestry, mining, rail, cranes, pumps, stationary power, marine, you name it and we’ve probably got a build for it!

It’s plain to see that Cummins 6CT engines have an incredibly wide range of applications; it’s no wonder these engines have become so popular in so many different industries.

Cummins 6CT Spec

Engine Data

Configuration Inline 6 Cylinder
Displacement 8.3 L, 504.5 cubic inches
Bore x Stroke 4.49" x 5.32"
Cylinder Head Cast Iron
Engine Block Cast Iron
Firing Order 1-5-3-6-2-4
Compression Ratio 17.5 : 1
Injection Direct Injection, Mechanical Injection Pump
Aspiration Turbocharged, wastegate controlled
Valve Train OHV, 2 valves per cylinder (ISC/QSC has 4 valve design)
Weight 1512 lbs without oil, depending on model
Oil Capacity 20 quarts
Governor Speed Varies with application
Horsepower 215HP to 300HP Extended Long Blocks
Torque 660-1200 ft/lbs. depending on model


Give us a call today at 844-340-4114 for immediate sales and support for the Cummins 4BT, Cummins 6BT, 6CT, ISC, 855, QSB 4.5 L or CAT 3306. If you have any questions check out our FAQ Page. We are always ready to help or just listen to your crazy off-roading adventures!

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Cummins 6CT Engines Gallery

Cummins 6CT
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Cummins 6CT Long Block 1
6CT 260HP Extended Long Block D
Cummins 6CT Engine

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