Driving Innovation In Diesel Performance

Heavy Hauler Long Blocks. Built for Cummins.

The Heavy Hauler is the ultimate workhorse long block comes with upgrades head and camshaft.

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Price $14,818.99
Heavy Hauler 2019+ Long Block

Heavy Hauler 2019+ Long Block

  • Fully assembled long block with oil pan and covers
  • 200 CFM Stage 1 head + tow cam for airflow
  • Solid tappets + adjustable rockers (2018-style reliability)
  • Pre-lubed and pressure-checked before shipping
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Price $12,730.99
Heavy Hauler 6.7 Cummins Common Rail Long Block

Heavy Hauler 6.7 Cummins Common Rail Long Block

  • Fully assembled long block with oil pan installed
  • 200 CFM Stage 1 cylinder head included
  • Street/towing camshaft for airflow under load
  • Pre-lubed with break-in oil + filter included
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Price $12,730.99
Heavy Hauler 5.9 Cummins Common Rail Long Block

Heavy Hauler 5.9 Cummins Common Rail Long Block

  • Fully assembled long block with oil pan installed
  • 200 CFM Stage 1 cylinder head included
  • Street/towing camshaft for airflow under load
  • Pre-lubed with break-in oil + filter included
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Price $12,731.23
Heavy Hauler 12v P-Pump Long Block

Heavy Hauler 12v P-Pump Long Block

  • Fully assembled long block with oil pan and covers
  • HP reman head (new casting) with CNC valve job
  • ARP 625 head studs + HD 7/16 pushrods installed
  • Pre-lubed and pressure-checked before shipping
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KNOWLEDGE HUB

Everything you need to know about D&J Cummins heavy hauler engines.

Heavy Hauler is built for the real world: towing, hauling, and long days on the job. The platform is designed to improve airflow (often referenced as a 200–300° EGT drop with the tow cam + head package) and includes blueprint/balance steps, pre-lube, and pressure checks to support a clean install and confident first start.

  • The Ultimate Workhorse Built specifically for demanding work trucks that need airflow, efficiency, and durability.
  • Stage 1 Cylinder Head Package Stage 1 head package is included to improve airflow and durability-focused sealing.
  • Tow Cam for Lower EGT Street/towing cam is listed as typically dropping EGT by 200–300° and improving fuel economy.
  • Sealing + Strength Upgrades Built with heavy-duty 7/16 pushrods plus head studs and main studs for durability under load.
  • Blueprinted and Balanced Engines are blueprinted/balanced with oil clearance measured and rings file-fit.

FAQs

What is a Heavy Hauler Cummins long block?
A fully assembled work-truck long block with a Stage 1 head, tow cam, and durability upgrades for airflow and sealing.
What engines are available in the Heavy Hauler lineup?
This collection includes Heavy Hauler long blocks for 5.9 CR, 6.7 CR, 2019+ 6.7, and a 12V P-Pump option.
Does Heavy Hauler include a Stage 1 cylinder head?
Yes, Stage 1 high-performance cylinder head is listed on the 5.9 CR, 6.7 CR, and 2019+ Heavy Hauler long blocks.
Will Heavy Hauler help lower EGTs for towing?
The tow cam + head package is listed as typically reducing EGT by 200–300 degrees and improving fuel economy.
What sealing upgrades are included?
The build lists include upgraded head studs and main studs, plus durability-focused cylinder head upgrades.
Do the engines ship pre-lubed?
Yes, listed as painted black and shipped pre-lubed with break-in oil and filter included.
Are Heavy Hauler long blocks pressure-checked?
Yes, cooling system and crankcase are listed as pressure-checked to ensure no leaks on installation.
What is the horsepower rating for Heavy Hauler?
The Heavy Hauler long blocks are listed as rated up to 700 hp (application and supporting mods still matter).