Diesel CNG Conversion Advantages


  • Reduces fuel costs approximately 35%
  • The diesel system injects natural gas "post turbo" into the intake manifold using an inline air mixture to draw in the air/natural gas blend into the cylinders.  This combination is more dense than just air and produces more power when compressed at the 18-1 ratio.
  • Diesel conversions don't have issues with pre detonation nor do they need knock sensors.
  • CNG is non corrosive and protects the engine from reactive contaminates.
  • The cleaner burning CNG and diesel mixture extends the time between replacing gallons of costly oil and filter changes.
  • Doubles your driving range
  • Vehicles operate more quietly

Electronic System

 Our electronic duel system works with any diesel engine; including tractor trailers & light duty trucks.  We gather many OEM sensor readings including an exhaust temperature sensor to ensure the safe operation of your engine. 

Diesel Fuel Replacement

 Our system has been precisely engineered to see results averaging 60% CNG fuel displacement and LPG averaging 40% displacement! 

User-Friendly Software

 Our advanced software has the ability to custom program settings of the alternative fuel system including switch over time, exhaust temp cutoff, mixture control, and more! 

Proven Technology

 Our dual fuel system has been tested on many continents around the world. With great results being proven it has been verified we have engineered one of the best (if not the best) dual fuel system on the planet. 

Key features


  • Sequential injection system for diesel
  • Works on ALL diesel engines
  • Easy to use software & Simple Installation
  • Automatic Diesel -> CNG/LPG switchover
  • Automatic CNG/LPG -> Diesel switchover if empty tank
  • Self diagnostic ECU. Up to 32 errors saved in memory
  • Sensors pre-define feature
  • Up to 6 pressure sensors defined
  • Up to 7 Vacum/Boost sensors defined


  • Able to read signals from TPS, Air-Flow meter, RPM signal, EGT sensor
  • 12V compatible, 24V compatible
  • European TIR compatible
  • Long cables for semi trucks, TIR
  • CDi/DCi/HDi/TDi emulator’s built into the ECU
  • Safety features to eliminate the possibility of engine failure
  • Full LPG/CNG level gauge + setup. You can define any level sensor you want (resistance, Hall, V, etc.)
  • Simple mixture map – for beginners/average users
  • Up to 8 temperature sensors defined


  • Diesel operation time
  • LPG/CNG work time
  • Advanced rpm setup 2 inputs; one input 
    varible 0-14 VDC
  • 5 emulators (3 analog, 2 digital – compatible with frequency digital signal)
  • OBD CAN compatible
  • advanced cut-off functions (including reading of diesel injection time)
  • full system diagnostic– switch test
    – level sensor/manometer test
    – emulators diagnostics
    – testing gas hoses for leakage
  • 3 advanced maps – for advanced users
  • EGT sensor included in the set (premium version)
  • And much more…

Replaces an average of 60% Diesel Fuel with CNG!

 Gratec Diesel Dual Fuel conversion system.  Our engineers have successfully created the best dual fuel conversion system on the market today. Our dual fuel system has logged substitution rates of up to 70% diesel fuel for the more cost effective CNG.  CNG is not only more cost effective but will also turn your dirty diesel engine into a cleaner burning vehicle.

The Gratec diesel dual fuel system works on diesel engines of all sizes. Whether you drive a diesel pick-up truck or a big rig semi tractor trailer this conversion system will work for you. Our engineers have not only surpassed the goals we set in place they also have successfully created one of the best (if not the best) dual fuel conversion system on the marketplace. 

 Our system monitors many OEM sensors to ensure the vehicle is running in ideal condition and not causing damage to your engine; we also add an additional EGT sensor to monitor exhaust temperature. Our system is OBD-2/CAN compatible and will work on 12V or 24V systems. This system is fully electronic and gives the the fleet manager the ability to monitor their drivers use of the CNG/ LPG dual fuel system.

On average we are consistently seeing 50-60% displacement of diesel fuel during normal driving operation. When running our LPG dual fuel system (due to less BTU) we are seeing on average a 40% displacement of diesel fuel.  Our system removes the driver from the equation and gives the fleet owner the guaranteed savings of the system.  With our competitive pricing, converting your fleet or vehicle with our dual fuel conversion kit is a smart, cost effective solution to saving money for your fleet fuel costs. 

No loss in Torque or Horsepower

 A common problem with dual fuel systems that get high diesel reduction percentages is their lack of torque and horsepower.  As you can see on the graph to the right our system does not loose any horsepower or torque while running our dual fuel mixture. Our mixture is very aggressive (average 60% mixture with CNG) however as the graph shows we are not taking away any power or torque the engine originally had.  The graph shows horsepower and torque when running on all diesel compared to running on the CNG blend. When running LPG results are comparable to CNG; once again there is no loss in horsepower or torque. If you would like to see the tested graph while running LPG simply contact us and we will be happy to provide you with the information.  We also have more dyno testing, DDEC testing, exhaust temperature and mixture tests that were performed at a US testing facility.