Frame-Rail Mounted CNG Fuel System

For Medium- and Heavy-Duty Trucks

Available in 41.2 and 46.5 DGE, Q-Rail features a sleek, aerodynamic, OEM-quality design that’s extremely lightweight and incredibly durable. Q-Rail is grid-friendly, and its hook-and-hang mounting make it easy to install. It is fitted with Q-Lite® tanks—the lightest in the industry—and comes with a 2-year 200,000-mile warranty.


  • Available in 41.2 DGE and 46.5 DGE
  • Sleek aerodynamic design
  • Short and extremely lightweight
  • Robust with increased durability
  • Grid-friendly design
  • Easy to install with “hook and hang” mounting mechanism
  • A safety switch detects if the door is left open, prohibiting the vehicle from starting
  • Configurable stepping bars (full, partial length or delete)
  • Equipped with one Q-Lite® tank, the lightest CNG tank in the industry
  • Automotive grade OEM white paint standard. Custom paint colors available
  • 2-year 200,000 mile warranty
Side Rail CNG
side rail cng system

Features and Benefits

Quantum’s culture of innovation continues to improve the efficiency of alternative vehicle technology. We make vehicles go farther; we increase storage capacity and reduce weight; we improve service and customer experience; we lower your overall cost of investment. Because we manufacture our own components, as well as design, engineer and develop our own fuel and control systems, we provide the best value in the industry.

Lightest Systems & Tanks
Quantum Q-Lite® tanks, Q-Rail and Q-Cab fuel system modules are the industries lightest.

Lightest Systems & Tanks

Highest Capacity Tanks
Optimized composite shell enables us to store more fuel.

Highest Capacity Tanks

Highest Quality Products
Our Q-Cab fuel system module completed 1 million miles of durability testing.

Highest Quality Products


Product Description Q-Rail 41 Q-Rail 41 Q-RAIL 46 Q-Rail 46
Part Number 117053 117059 116883 116942
Diesel Gallon Equiv. (IA) DGE 41 41 46 46
Module Length Inches 89 85 99 95
Module Height Inches 28 28 28 28
Module Depth Inches 34 34 34 34
Q-Lite Tank Installed Units 25×80 25×80 25×90 25×90
Fill Location Left Fill n/a Left Fill n/a
Module Type Fill Expansion Fill Expansion
Module Fill Panel Yes N/A Yes N/A
Regulator Included Yes N/A Yes N/A
High Flow Fill System Yes N/A Yes N/A
Module Weight – empty lbs 520 492 572 544
Gass Mass lbs 225 225 255 255
Total Weight lbs 745 717 827 799
Range @ 6 mpg miles 210 210 237 237
Usable Gas Mass @ 290-3600 psi lbs 195 195 221 221
Gasoline Gallon Equiv. (NIST) GGE 39.7 39.7 45.0 45.0

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What Our Customers Say?

We chose Quantum because they really listened to our needs and their system gives us the best value in regards to weight and price
Juan Corcino
Director of Fleet/OPS, ManhattanBeer Distributors

The Quantum Warranty

We stand behind every product we make. Our Fuel System are backed by a two-year/ 200,000-mile warranty. With no deductible or service charges, it’s one of the most comprehensive warranties in the industry, plus it’s fully transferable during the warranty period. Our more than 20 years in the clean fuel vehicle business prove that we’ll be here to service your needs for many years to come.

Quantum Service Network

We’re constantly expanding our service network to help our customers more efficiently. If you’re interested in becoming an authorized Quantum Service Center, contact us.

Service Centers

Our customer service is second to none. We know the importance of keeping your trucks on the road; our Service Team will assist you in doing just that. With 20+ years in the CNG industry our service team has the knowledge and experience to help your technicians diagnose a problem and get parts for a quick repair turn around. Partnering with service centers, we leverage a broad range of capabilities to efficiently maintain and repair your vehicle and increase your uptime.

For a service center near you, call 1-800-816-8691.


Quantum’s Type IV tanks are validated by the stringent requirements of NGV2, and our systems comply with or exceed all applicable industry standards. But Quantum goes beyond industry requirements to ensure safety and reliability—and beyond any other fuel system provider—with the most rigorous thermal, shock, vibration, impact, and corrosion, testing in the industry.

Why Natural Gas?