Story and photos by Robby DeGraff
Looking to drive a bit greener? Check off the $11,000 compressed-natural-gas option package on the Ram 2500 crew-cab 4x4, and you get a standard 5.7-liter V-8 Hemi engine and a 260-liter CNG tank in the bed that Ram says is good for an estimated 255 miles of pure, clean driving.
Range anxiety is gone in this alternative-fuel vehicle because when the CNG tank (equal to about 18.2 gallons) runs empty, the transition 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 small gas tank there as a “just in case” measure for fleet drivers if they don’t make it 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. Total combined range for both tanks is around 370 miles. We should 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) for under $2, but we found quite a bit of variation among pumping stations. But how realistic is this alternative?
With only 519 registered filling stations in the United States to date, we set out to see if a CNG truck is comfortable and convenient for everyday use.
First off, this Ram is a big boy. The setup Ram offers with the CNG option is a 2500 HD crew cab and 8-foot bed. Why the long bed? The CNG option 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 can support quite a bit of weight. Attractive-looking CNG livery dons both sides of the rear bed, and a blue diamond-shaped CNG badge appears on the tailgate.
This heavy-duty truck — ours weighed 7,540 pounds — still packs the tough attitude of a Ram, but expect to feel a slight dip in power when 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, you will notice a power difference, yet not dramatic one, in overall power, as well as in engine noise.
[Editor’s note: We took the setup to a trusted dyno — thank you, K&N Engineering — and found that the actual horsepower differential was 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, fall morning in Wisconsin at 40 degrees, I left behind, what looked like, trails of steam, and it took a 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 a few 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 filler clamps and payment issues are just a few. While there are only two CNG stations in the Chicago area, there are nearly seven in Milwaukee.
After checking an online fuel price source and the CNG Now app on my iPhone, I went to a station described as a 24-hour public access station run by We Energies. It looked closed. I got out and walked around to see if I could speak with the facility manager, but no luck. A security guard at the station told me it was closed and that I would need permission with supervision to fill up a CNG vehicle here in the future. The second station, which was easily accessible and open, also gave us troubles. Even though I was told (via phone) we could pay 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 a Mobil station sold CNG at $1.98 per gge. It looked like our light at the end of the tunnel. Filling up the Ram here was easy, quick and simple. There are usually two pumps for CNG — one operating at 3,600 psi and the other at 3,000 psi. Our Ram 2500 required the higher pressure for a full refill, but if you’re in a pinch, you can fill up with either. A lower psi means you won’t get as much distance out of a full tank. Both pumps were modern-looking and took credit-card payments, just like you would do filling up with gas.
A community shuttle-bus driver asked me about the truck, and he was kind enough to show me the proper way to fill with CNG. “You want to make sure you keep your face away from here,” he said, inserting the yellow plug 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’s nipple. Both the capless gas tank and CNG filler nipple sit behind the same tank door; it would be better if this truck had its own separate CNG cap area and gave you a little more room to clamp the nozzle onto the filler nipple. Once the pump clamp is attached, the pump hisses and whirrs loudly for a few seconds as it analyzes pressure inside the Ram’s two CNG tanks, then it cycles the CNG with the pressure pump, filling the tanks equally.
It took a little under 10 minutes for the pressure inside the tanks to reach full (identified on the pump as a percentage). Turning the blue handle to “vent,” a short hiss sounded as I returned the CNG hose back to the pump. The total, 18.04 gge of CNG cost $35.89. If I filled the truck’s standard eight-gallon gasoline tank, the total would still be under $67.
How much would it cost to fill up the regular gas-only Ram 2500’s 35-gallon fuel tank? $139.30.
Will fleets and hard-hat workers, who sometimes drive more than 30,000 miles a year, drop an extra $11,000 for the CNG option on the Ram 2500? We think so. After a bit of math, we figured that on average, you could save nearly $4,000 a year on fuel by opting for CNG. After driving just three years, the cost savings would offset this alternative-fuel option. Of course, fleet operators usually run very different duty cycles compared with normal truck drivers, but depending on where and how you drive, we could see this being a viable option for some regular pickup truck consumers.
Still, $11,000 for the bi-fuel option may be a little much for most people. Our SLT crew cab 4x4’s base price was $41,000, but once you check all the boxes for this work-duty HD, the price hits just under $58,000 (Download 2012 Ram 2500 CNG monroney).
After a few rough patches, we’re now big fans of CNG, and it seems like a reasonable idea. But where we live, the infrastructure needs to make a little more progress to make filling up easier, more reliable and simpler to pay for.