When it’s time to replace or upgrade the engine in your Cummins, the amount of options can be totally overwhelming. Are you just looking for a reliable replacement for your work truck, or are you looking for something more performance based? 

At D&J Precision Machine, we don’t believe in a one size fits all option. Every engine we build is a product of CNC machined precision and real world testing. To help you decide, we’ve broken down our three most popular Cummins crate engine collections so you can find the perfect foundation for your build, one that is unique to you and how you use it. 

1. The Heavy Hauler

If your truck spends its life hitched to a 15,000-lb fifth wheel or a gooseneck trailer, the Heavy Hauler is the engine for you.

While the factory Cummins is a great engine (obviously you know this or you wouldn't have bought it in the first place), it can struggle with heat and airflow when pushed to the limit under a heavy load. The Heavy Hauler addresses this with our Stage 1 Head, featuring heavy-duty valve seats and improved flow.

• The Big Benefit: Our customers typically see a 200–300°F drop in EGTs (Exhaust Gas Temperatures).

• Why it Matters: Lower EGTs mean less stress on your turbo and internal components, ensuring you stay on the road instead of in the shop.

• Best For: Hot shot drivers, farmers, and those who love to travel with their RV. A great option for longevity and reliability.  

2. Street Performance

Maybe you aren't heavy hauling every day, but you want a truck that’s fun to drive with a little boost. The Street Performance collection is designed for the enthusiast who wants a peppy feel and a foundation that can handle mild tuning and aftermarket turbos without issue. 

• The Build: Includes upgraded rods and pistons designed to handle higher cylinder pressures than the stock OEM setup.

• The Vibe: It’s smooth, reliable, and provides peace of mind when you decide to floor it. 

• Best For: Daily drivers, weekend racers, and anyone looking for a significant step up from a stock rebuild.

3. The Predator, Enforcer, & Executioner

For those who live at the drag strip or the pulling track, we have the Predator and Enforcer series. These engines share the same DNA as our record breaking Executioner engine (capable of 3,000+ HP).

• The Tech: These builds often feature our fully deck-plated blocks, custom billet components, and extreme-duty valvetrains.

• The Goal: To survive the kind of heat and pressure that would melt a standard block in seconds.

• Best For: Competition level sled pulling, drag racing, and high horsepower builds where too much  is never enough! 

How Do You Want It Delivered?

Once you’ve picked your performance collection, you have one more choice: Long Block or a Ready Run Complete Engine Package.

• The Long Block: We provide the short block (bottom end) and the cylinder head. You swap over your existing fuel system, turbo, and accessories. This is the most cost effective way to get a D&J engine if your bolt-on parts are still in good shape.

• The Ready Run: We do the heavy lifting. Your engine arrives fully assembled with the turbo, manifold, and fuel system already installed. It’s the fastest way to get your truck back on the road with the confidence that every single bolt was torqued by a D&J professional.

The Bottom Line

Whether you’re towing a camper across the country or chasing a world record on the track, we have a foundation built for your specific needs and wants! 

Click here to find the right crate engine for your wants and needs!