Skip the Premium at the Pump this Holiday SeasonDecember 3rd, 2014 by Rachel Sheelam
Ahh, the holidays. Now is the time of year we come together with our families and friends and celebrate the things we love most in our lives. The holidays also mean lots of snow to play in if you’re an off-roader, and if you’re not it still means a lot of driving for holiday shopping and family visits. ‘Tis the season to fill up on pie and eggnog … and the season to fill up the gas tank. But before you hit that “premium” button, there are some things you should know.
Research has pretty conclusively shown that running mid-grade or premium fuel in an engine which does not require it has next to no impact on daily driving. Why is this and what about for off-roading? Do you need a higher grade of fuel if you’re climbing steep inclines and taking on tough obstacles on the trail? Does it help your engine run cleaner and smoother? Does it give you extra ‘oomph’?
The short answer is no, and here’s why:
According to the Federal Trade Commission, “The recommended gasoline for most cars is regular octane. In fact, in most cases, using a higher octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage, or run cleaner.”
Fuel with a higher octane level, aka ‘premium’ fuel, can withstand greater pressure and higher temperatures before combusting. If you own a luxury sports car or your engine is up there in years, using a low-grade fuel can cause it to “knock”.
Engine knocking is when the fuel in the engine’s piston combusts prematurely. This can be due to hot spots in the piston or, if you have a luxury or sports vehicle with a high compression engine, too low a fuel grade being used. However, the vast majority of vehicles, including the ones used for off-roading, are designed for regular fuel, so over-compression should not be an issue. Also, modern vehicles are equipped with knock sensors, which “listen” for engine knocks and adjust the timing* to make them stop over time.
Knock sensors work to prevent engine knocking when running low-grade fuel in your engine by adjusting timing*, but it will not work in the reverse direction. That is to say, putting premium fuel in a regular engine will not cause that engine to compress to premium fuel levels. It will run exactly the same as it did with the regular fuel.
Premium fuel does not provide your engine with more power any more than it increases fuel efficiency, unless you have a high compression engine. In this case, your owner’s manual should mention a need for premium.
If your engine isn’t knocking, switching to premium fuel won’t do you a lick of good. So go ahead, hit the ‘regular’ button at the pump and use the money you save to buy yourself some new parts – like an ATV snow plow so you can finally stop shoveling your driveway.
*Update: Originally, this segment stated that knock sensors adjusted compression. I did, unfortunately, misspeak here – a big thank you to our Facebook fans for pointing out the error so it could be corrected!
About the Author: Rachel Sheelam
The 4x4 and off-road lifestyle was all new to me when I first joined this team, but in the year since then I have developed a true passion for the automotive industry. I've learned more than I knew there was to know about trucks, Jeeps and SUVs - from suspension articulation physics to which types of tires are the best for wallowing in the mud. Whether it's the latest in automotive technology or the best 4x4's in film, I'm always on the lookout for the next big learning curve or news to share. You can keep up with me on my adventure into 4-wheeled life on Google Plus: https://plus.google.com/u/0/+RachelBowesatTAP/posts