Beyond Diesel and Electric: Natural Gas and Dual-Source Options Now on the Dump Truck Spec Sheet

For the past couple of years, the powertrain conversation around dump trucks and mixers has mostly been framed as a binary choice: stick with diesel, or go electric. That framing has always undersold the actual menu of options available across the four brands BFC finances. Two developments worth putting side by side show a third lane opening up — one that doesn't require the range limitations, charging infrastructure investment, or comparatively short resale history that come with a fully electric truck today: Freightliner's dedicated 114SD Natural Gas chassis, and Mack's new Cummins X10 option on the Granite, a dual-source arrangement that pairs an outside engine with a torque-converter automatic rather than Mack's own in-house diesel and automated manual.

The Natural Gas Lane: Freightliner's 114SD Natural Gas

Freightliner's 114SD Natural Gas runs a Cummins Westport ISL G, an 8.9-liter spark-ignited engine built specifically to burn natural gas rather than adapted from a diesel platform. It's rated across a 260 to 400 horsepower band with up to 1,450 lb-ft of torque, pairs with an Allison 3000 RDS automatic, and carries a 62,000 lb GVWR — squarely in the Class 7/8 range a lot of construction dump and mixer work falls into. We've covered this chassis in more detail separately, but the headline point worth repeating here is that it's a genuinely different approach to lowering emissions than electrification: a combustion engine that burns a cleaner fuel, rather than eliminating combustion altogether.

The Dual-Source Lane: Mack's Cummins X10 and Allison Pairing

Mack's move is philosophically different but points in a related direction: for the first time, the Granite can be ordered with a Cummins X10 engine — a 10-liter diesel rated from 350 to 450 horsepower and 1,250 to 1,650 lb-ft of torque — paired with an Allison 3000 or 4000 Series true torque-converter automatic, instead of Mack's own in-house MP13 and mDRIVE HD automated manual. This isn't an alternative-fuel story the way the 114SD Natural Gas is; it's still diesel. What it represents is manufacturers becoming more willing to offer outside powertrain components on their flagship vocational platforms, rather than insisting on a single, fully in-house solution — which widens the realistic options available to a buyer with a specific duty-cycle preference, like wanting Allison's torque-converter smoothness without leaving the Mack badge behind.

Why Both Developments Matter Together

Looked at individually, these are two fairly narrow spec-sheet updates on two different trucks. Looked at together, they suggest the industry's response to tightening emissions standards and shifting buyer preferences isn't converging on a single answer the way a lot of electric-vehicle coverage implies. Some manufacturers and buyers are betting on full electrification for the right duty cycles. Others are finding real value in cleaner-burning alternative fuels like natural gas that don't require rebuilding a fleet's fueling infrastructure from scratch. And some are simply opening up more combinations of proven, conventional components — outside engines, outside transmissions — to give buyers more ways to match a powertrain to a specific duty cycle without waiting for a fully new fuel type to mature.

How to Think About Infrastructure for Each Path

Electric trucks require charging infrastructure investment, which we've covered separately in the context of Florida Power & Light's Make-Ready Credit Program that offsets some of that cost. Natural gas requires CNG fueling access, which is a narrower but in some ways simpler infrastructure question — a fleet near an existing public CNG station, or large enough to justify its own fueling setup, can realistically run the 114SD Natural Gas without the same from-scratch electrical infrastructure buildout an electric fleet needs. The Cummins X10 and Allison pairing on the Granite requires no new infrastructure at all — it's still diesel, fueled anywhere diesel is sold, which makes it the lowest-friction of the three paths for a fleet that wants a meaningfully different driving experience without any infrastructure planning whatsoever.

Matching the Path to Your Actual Operation

A municipal or utility fleet that already runs CNG vehicles and has fueling infrastructure in place is a strong fit for the 114SD Natural Gas. A short-haul urban fleet with a predictable daily range and either existing charging infrastructure or access to credit programs that offset the buildout cost is a strong fit for an electric platform like the eMV or eM2. And a ready-mix or demolition fleet that simply wants Allison's torque-converter smoothness on a Mack chassis, without changing fuel type or adding any infrastructure, is exactly who the Cummins X10 pairing is built for. None of these is a universally correct answer — they're three different ways manufacturers are responding to the same underlying pressure, and the right one depends entirely on your routes, your existing infrastructure, and your tolerance for being an early adopter on a less common configuration.

A Side-by-Side Snapshot

The 114SD Natural Gas runs a Cummins Westport ISL G at 260 to 400 horsepower and up to 1,450 lb-ft of torque, on a 62,000 lb GVWR, paired with an Allison 3000 RDS automatic. The Granite with the Cummins X10 option runs 350 to 450 horsepower and 1,250 to 1,650 lb-ft of torque, paired with an Allison 3000 or 4000 Series automatic, on a chassis whose Class 8 GVWR ceiling runs meaningfully higher than the natural gas Freightliner's. Mack's own EPA27 MP13 tops both, at up to 540 horsepower and 1,950 lb-ft. Laid out this way, the real pattern is that each option occupies a different slot in the weight and power spectrum, rather than directly competing with each other — a buyer isn't really choosing among these three as equivalent substitutes, but matching each to a specific GVWR need and fuel-infrastructure reality.

What's Likely Coming Next

Given that both of these developments landed within the same general period, it's reasonable to expect other manufacturers to widen their own powertrain menus in similar ways rather than funneling every alternative-powertrain buyer straight to electric. International and Kenworth haven't announced comparable dedicated natural gas or dual-sourced diesel-and-Allison options on their current dump and mixer platforms as of this writing, but the direction Freightliner and Mack have each taken suggests buyers should keep asking their dealers directly about what's available, rather than assuming the powertrain conversation begins and ends with diesel or electric.

Resale Considerations Across All Three Paths

Diesel, in any configuration, still carries the deepest and most liquid resale market of the three paths — which is part of why the Cummins X10 pairing on the Granite is the lowest-risk alternative-powertrain bet of the three from a pure resale standpoint. Natural gas chassis carry a narrower resale pool than standard diesel, concentrated among fleets with existing CNG access. Electric trucks carry the shortest track record of the three, which is exactly the lending consideration we've covered in our broader look at how lenders evaluate electric and alternative-fuel vocational trucks. None of this should discourage a fleet with a genuinely good infrastructure and duty-cycle fit from choosing natural gas or electric — it's simply a factor worth weighing honestly against the lowest-friction, diesel-based Cummins X10 option if infrastructure access is still uncertain.

A Practical Starting Point if You're Unsure

If none of these three paths feels like an obvious fit yet, the practical starting point is an honest inventory of your own infrastructure and routes rather than the powertrain itself: do you have, or can you reasonably build, CNG fueling access; do you have, or can you secure through a program like FPL's Make-Ready Credit, electric charging infrastructure; and is your primary interest in trying something new actually about emissions and fuel cost, or about a specific driving characteristic like Allison's torque-converter smoothness. Answering those questions honestly generally points toward one of these three paths more clearly than comparing horsepower numbers across all of them at once.

Rent-vs-Own Across a Widening Menu of Options

A wider menu of powertrain options is actually a reasonable argument for ownership over renting, not against it: a rental fleet is far less likely to stock the specific alternative-powertrain configuration that best fits your operation, which means renting often means settling for a generic diesel configuration regardless of what would genuinely serve your routes best. Financing lets you actually spec the powertrain that fits, whether that's natural gas, a dual-source diesel-and-Allison pairing, or standard diesel.

Don't Let the Options Paralyze a Decision You Need to Make Now

A wider menu of choices is a genuine positive for buyers, but it can also become a source of analysis paralysis for a contractor who needs a working truck on a specific timeline. If your business doesn't already have natural gas or electric charging infrastructure, and building either is not realistic in the near term, the standard diesel configuration on any of these four brands remains a perfectly sound choice, and the Cummins X10 and Allison pairing on the Granite specifically gives you a meaningfully different driving experience without requiring any infrastructure decision at all. Don't let the existence of more exotic options talk you out of a straightforward diesel purchase if that's genuinely what fits your operation today.

Financing Any of These Powertrain Paths

BFC structures equipment financing and equipment leasing across the full range of powertrain options now available on Kenworth, Mack, International, and Freightliner chassis. For more detail on each path covered here, see our spotlights on the Freightliner 114SD Natural Gas and Mack's Cummins X10 and Allison pairing, and our broader coverage of how lenders evaluate electric and alternative-fuel vocational trucks for the electric side of this comparison.

Ready to Put This Truck to Work?

Whether you are financing your first truck or adding another chassis to a growing fleet, BFC Equipment Loans structures equipment financing and equipment leasing specifically for construction, hauling, and ready-mix operators. Visit our home page to learn more about how we work, or go straight to our equipment financing application if you are ready to get started. Browse current dump trucks, mixer trucks, and other equipment for sale in our inventory marketplace, and subscribe to our blog for more coverage of Kenworth, Mack, International, and Freightliner trucks as new models and financing options come available.