Story and photos by Robby DeGraff
Looking to drive a bit greener? Check off the $11,000 compressed-natural-gasoption package on the Ram 2500 crew-cab 4×4, and you get a standard 5.7-literV-8 Hemi engine and a 260-liter CNG tank in the bed that Ram says is good for anestimated 255 miles of pure, clean driving.
Range anxiety is gone in this alternative-fuel vehiclebecause when the CNG tank (equal to about 18.2 gallons) runs empty, thetransition to gasoline is mostly seamless, apart from the return of that burly,muscular Hemi sound and power. Ram tells us that fleet buyers want the smallgas tank there as a “just in case” measure for fleet drivers if they don’t makeit all the way back to company headquarters to refill the tank with less-expensive CNG.
The small, eight-gallon gas tank offers just over 100 miles of range. Totalcombined range for both tanks is around 370 miles. Weshould note that Ram does offer a regular 35-gallon tank as a $350 option.
The immediate and long-term cost savings can be tremendous,with most CNG stations selling one gallon of gasoline equivalent (gge) forunder $2, but we found quite a bit of variation among pumping stations. But howrealistic is this alternative?
With only 519 registered filling stations inthe United States to date, we set out to see if a CNG truck is comfortable andconvenient for everyday use.
First off, this Ram is a big boy. The setup Ram offers withthe CNG option is a 2500 HD crew cab and 8-foot bed. Why the long bed? The CNGoption puts a steel enclosed box in the bed to house the two CNG tanks.Unfortunately, you lose about half of the cargo space, but the box itself cansupport quite a bit of weight. Attractive-looking CNG livery dons both sides ofthe rear bed, and a blue diamond-shaped CNG badge appears on the tailgate.
This heavy-duty truck — ours weighed 7,540 pounds — stillpacks the tough attitude of a Ram, but expect to feel a slight dip in powerwhen running CNG. The setup is designed primarily to run on CNG when available,then switch to gasoline when the CNG is depleted. When that switch happens, youwill notice a power difference, yet not dramatic one, in overall power, as wellas in engine noise.
[Editor’s note:We took the setup to a trusted dyno — thankyou, K&N Engineering — and found that the actual horsepower differentialwas 13 percent (33 hp) less rear-wheel horsepower and 10 percent less torque(26 pounds-feet) on CNG compared with gasoline. Some may remember when we tested a Ford Super Duty Westport bi-fuel system with the 6.2L V-8; that system recorded a horsepower percentage differential between CNG and gas of 15 percent, and a torque differential of 18 percent.]
We didn’t mind the change in sound, though. That unique “whishing”sound almost reminded us of a turbine jet engine at times. On a cold, fallmorning in Wisconsin at 40 degrees, I left behind, what looked like, trails of steam, and it tooka few minutes for the Ram coolant to warm up enough to get the CNG (which tends to cool when going from a compressed state to less pressure) to the right–warmer–temperature.
The system starts with gasoline if the engine and coolant temperature is below 50-degrees Fahrenheit then moves to CNG once the parameters are met. As to what we saw coming out the tailpipe, it looked as clean as we've ever seen. Although we know the same chemical compounds are coming out the tailpipe as would when running on gasoline, we know there is a lot less of it.
As we drove through the picturesque Kettle Moraine forest,it was good to know that we were burning clean fuel, but we did experience afew issues issues when refueling.
Filling up a vehicle with CNG is not easy for several reasons.Irregular pressure, closed pumps, awkwardly stiff hoses, ill-fitting fillerclamps and payment issues are just a few. While there are only two CNG stationsin the Chicago area, there are nearly seven in Milwaukee.
After checking an online fuel price source andthe CNGNow app on my iPhone, I went to a station described as a 24-hour public access stationrun by We Energies. It looked closed. I got out and walked around to see if Icould speak with the facility manager, but no luck. A security guard at thestation told me it was closed and that I would need permission with supervisionto fill up a CNG vehicle here in the future. The second station, which waseasily accessible and open, also gave us troubles. Even though I was told (via phone) we couldpay with a credit card, the CNG pump didn’t accept our plastic. So we headed out again.
Heading northbound, we stopped in West Bend, Wis., where aMobil station sold CNG at $1.98 per gge. It looked like our light at the end ofthe tunnel. Filling up the Ram here was easy, quick and simple. There areusually two pumps for CNG — one operating at 3,600 psi and the other at 3,000psi. Our Ram 2500 required the higher pressure for a full refill, but if you’rein a pinch, you can fill up with either. A lower psi means you won’t get asmuch distance out of a full tank. Both pumps were modern-looking and tookcredit-card payments, just like you would do filling up with gas.
A community shuttle-bus driver asked me about the truck, andhe was kind enough to show me the proper way to fill with CNG. “You want tomake sure you keep your face away from here,” he said, inserting the yellowplug into the filler area. Twice this weekend I had trouble fitting the pumps’CNG nozzle into the Ram’s tight filler area and clamping it onto our tank’snipple. Both the capless gas tank and CNG filler nipple sit behind the sametank door; it would be better if this truck had its own separate CNG cap areaand gave you a little more room to clamp the nozzle onto the filler nipple. Oncethe pump clamp is attached, the pump hisses and whirrs loudly for a few secondsas it analyzes pressure inside the Ram’s two CNG tanks, then it cycles the CNGwith the pressure pump, filling the tanks equally.
It took a little under 10 minutes for the pressure insidethe tanks to reach full (identified on the pump as a percentage). Turning theblue handle to “vent,” a short hiss sounded as I returned the CNG hose back tothe pump. The total, 18.04 gge of CNG cost $35.89. If I filled the truck’sstandard eight-gallon gasoline tank, the total would still be under $67.
How much would it cost to fill up the regular gas-only Ram2500’s 35-gallon fuel tank? $139.30.
Will fleets and hard-hat workers, who sometimes drive morethan 30,000 miles a year, drop an extra $11,000 for the CNG option on the Ram2500? We think so. After a bit of math, we figured that on average, you couldsave nearly $4,000 a year on fuel by opting for CNG. After driving just threeyears, the cost savings would offset this alternative-fuel option. Of course,fleet operators usually run very different duty cycles compared with normaltruck drivers, but depending on where and how you drive, we could see thisbeing a viable option for some regular pickup truck consumers.
Still, $11,000 for the bi-fuel option may be a little much formost people. Our SLT crew cab 4×4’s base price was $41,000, but once you check allthe boxes for this work-duty HD, the price hits just under $58,000 ().
After a few rough patches, we’re now big fans of CNG, and itseems like a reasonable idea. But where we live, the infrastructure needs tomake a little more progress to make filling up easier, more reliable andsimpler to pay for.
