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  • 2014 Ram 2500 Biodiesel Testing - Final Gear Editorial

2014 Ram 2500 Biodiesel Testing - Final Gear Editorial

Running On Commercial Bio

Jul 10, 2014
Diesel truck owners are an opinionated bunch who love to argue about seemingly anything. Don’t take my word for it; just spend five minutes on Facebook or any diesel forum. And nothing seems to divide the room quite like the talk of biodiesel. It appears that people are all over the board when it comes to running bio, from not a chance to every tank. Having never burned this renewable fuel myself, I decided it was time to throw down a couple of tanks just to see what the hype -- for and against --was all about.
I started my informal biodiesel test with a familiar face, a 2014 Ram 2500, the same truck used for our 1500 vs. 2500 test (“Sibling Rivalry,” March 2014). Why this truck you ask? For starters, the 6.7L Cummins that comes in the 2014 Ram trucks is rated for B20 from the factory. This meant, in theory, that we wouldn’t have any compatibility issues from running the fuel. Secondly, we already had performance and fuel economy data from this exact truck, making additional comparisons easy.
Photo 2/6   |   Biodiesel Pump
Before I get too far ahead of myself, we need to talk about the type of biodiesel used for this test. What most people associate with bio right now is more than likely homebrew, and that is where a lot of the misconceptions come from. When people produce biodiesel themselves, the quality of the finished product is not guaranteed. This type of fuel can cause issues in newer common-rail engines, which often lead to the horror stories on the Internet. It’s not just homebrewers, either; issues can develop from fuel produced by co-ops and other medium-output groups. The fuel we wanted to test is the commercially available kind, which you’ll find at the neighborhood fuel station.
In general, biodiesel provides a whole host of advantages for both engines and the environment. Commercially available bio ensures precise quality standards are met, meaning that running it will do no inadvertent damage. Biodiesel produces less carbon dioxide and monoxide emissions, as well as less particulate matter, which means less frequent DPF regeneration. It also provides better lubricity and a higher cetane rating than petroleum-based diesel. Best of all, at least on the West Coast, it’s priced less than standard number 2.
So why all the hate if there are so many positives? One criticism is that biodiesel clogs fuel filters. It is true that in higher-mileage diesels fuel filters will need to be changed more frequently when running biodiesel, but this isn’t because of the fuel itself. It’s due to the fact that biodiesel is a better solvent than petrodiesel and actually cleans the built-up gunk out of the truck’s fuel tank and system. The higher the concentration of biodiesel, the quicker the tank gets cleaned and the filter gets clogged. This leads directly to the second myth of biodiesel: that it provides less power and lower fuel economy. Typically, the cause of this is a clogged fuel filter. See the connection? Keep the filter clean, and you’ll never know there is bio in the tank.
Photo 3/6   |   Biodiesel Pump
This brings us back to my quick test. I saddled the truck up with the same trailer and load as before and hit the road. At first, it seemed like the engine was louder when running on B20, but after a few hours it all seemed normal. I attribute this simply to a placebo effect. I wanted there to be something noticeably different with the new fuel, so my brain said it was louder. The reality is after I switched back to number 2 the noise level remained the same. The truck’s power felt the same as well, and the truck had absolutely no issues hauling the load on level ground, or up steep hills. I even spanked a Duramax up the infamous Grapevine. With the tow test complete, I unhooked the trailer and ran a tank with the truck empty. Both tests returned fuel economy numbers that were within ½ mpg of the original test.
At the end of it all, the B20 biodiesel was less expensive, better for the environment, good for our truck’s engine, and returned the same power and fuel economy as regular old number 2. I’m really hoping this catches on, because having the option for bio at every pump would be awesome!