Ford 2004 Mustang Owner's Manual page 13

Use caution when fueling your vehicle. Make sure the engine is
turned off and all flammable material is extinguished. Observe all
Dispensing Equipment Safety Standards and Operating Procedures.
The procedure is the same for both fast-fill and slow-fill fueling.
1. Open fuel door and determine the pressure rating of your vehicle's
fuel system.
2. Remove protective cap from the vehicle's fuel receptacle. Remove any
debris that may be present.
3. Follow the natural gas fueling procedures provided by the natural gas
dealer and dispense the CNG until the fuel tanks are full or until the flow
stops.
4. When refueling is complete, follow the natural gas dispensing
equipment's operating procedures to shut the natural gas flow off.
5. Remove the dispensing connector and put protective cap on the
vehicle's fuel receptacle. Close the fuel door.
Refill capacities — BTU equivalent to gasoline
Fueling method Standard tank
Slow-fill 60.9L (16.1 gallons) 92.7L (24.5 gallons)
Fast-fill 51.8L (13.7 gallons) 78.7L (20.8 gallons)
Fueling method Standard tank
Slow-fill 70.0L (18.5 gallons) 106.0L (28.0 gallons)
Fast-fill 59.4L (15.7 gallons) 90.1L (23.8 gallons)
E-Series Cutaway 158" Wheelbase (3000 psi)
Fueling Standard
method tanks
Slow-fill 55.3L
(14.6 gallons)
Fast-fill 46.9L
(12.4 gallons)
Servicing your vehicle
E-Series (3000 psi)
With extended range tank
E-Series (3600 psi)
With extended range tank
With Extended
Range - One
In-body Tank
84.0L
(22.2 gallons)
71.2L
(18.8 gallons)
With Extended
Range - Two
In-body Tanks
112.4L
(29.7 gallons)
95.8L
(25.3 gallons)
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