For keeping your car or truck in optimal condition, following the manufacturer’s instructions and recommendations for its “care and feeding” will give your vehicle its best and longest life. Your Owner’s Manual will eliminate any guesswork about what gasoline to select at the pump and there are very good reasons not to try and second-guess something different, such as a flex-fuel for your ride.
One: Most gasoline vehicles are designed to run on 87 octane
The majority of vehicles on the road today are designed for regular, unleaded 87 octane gasoline. Unless your vehicle recommendation is for a higher-octane, premium fuel, there is no reason to opt for the higher fuel cost because under normal driving conditions, there is little to no benefit. Automakers recommend what type of gasoline to use for peak performance in your select vehicle, and most cars, trucks, and SUVs are efficient, without sacrificing performance, running on a diet of regular gasoline.
Two: “Required” fuel type is non-negotiable
When higher octane fuel is required/necessary to power high-performance engines, the Owner’s Manual will specify exactly what gas to use. Filling up with the right gas is so important that the dashboard gas gauge may give a reminder of the proper fuel as well a warning notice at the gas cap. When required, if you use less than premium-grade fuel with 91 to 94 octane, you could damage your engine. If you fill up with regular by mistake, you can add an octane booster additive to increase the octane rating to the required premium level for that tankful.
“Required” fuel type is also true for diesel or compression ignition engines. Petroleum distillate diesel fuel is required, or you will ruin the engine. Putting gasoline in a diesel engine can cause damage to the fuel pump, filter, and injectors. Likewise, if you put diesel fuel into a gasoline engine, it can cause the engine to seize up. If you ever accidentally put diesel in your gasoline engine car, drain the fuel tank ASAP, don’t drive around with diesel.
Three: “Recommended” fuel type gives some wiggle room
Recommended carries less weight than required, so while regular unleaded gasoline is recommended for most cars, using premium gas instead of 87 octane is an option that will not cause harm. Except to your wallet. The popular expectations of better fuel economy, improved performance, and reduced emissions from premium-grade fuel were largely refuted by AAA laboratory tests that “found no significant increases in any tested category, indicating the practice of using premium gasoline when it’s not required for the vehicle offers no advantage.” In 2016, U.S. drivers spent $2.1 billion needlessly on premium fuel to power regular unleaded engines. (Gas was cheaper then, imagine what it would be today!)
Although it’s safe to increase the octane rating of your gas if desired, using a lower octane fuel than recommended is not safe and will cause an engine to run poorly, damaging the engine and emissions control system over time. Driving on below-recommended octane will cause knocking or pinging in the engine, especially in older model cars. Using the wrong gas could also void your warranty if you end up needing engine repair caused or aggravated by using the wrong grade of gasoline.
Four: E85 flex-fuel is only safe for flex-fuel vehicles (FFV)
If your vehicle is not designed explicitly for flex-fuel, putting E85 in a car that isn’t designed for it can be harmful. E85 is a fuel composed of 85% ethanol and 15% gasoline that is designed to be used in flex-fuel vehicles with specially designed engines and fuel systems. Flex-fuel vehicles have basically given way to the promise of electric cars with only a handful of automakers selling new 2023 flex-fuel vehicles. There are, however, millions of used flex-fuel models from previous years if you want one without the new car price tag.
Controversy surrounds E85 as to whether or not it’s a smart move for performance, economy, and the environment. Here are salient points to consider before making a move to trying E85:
· You have to have or buy a flex-fuel vehicle.
· E85 flex-fuel is not nearly as common at fuel stations as regular gasoline and can sometimes be difficult to find. E85 pumps are clearly labeled at gas stations and typically have yellow nozzles to avoid mistakes.
· Mixing regular gas and flex-fuel in a regular gasoline engine can damage the engine and decrease performance and fuel economy. Cars that can accept flex-fuel will have a yellow gas cap or a yellow plastic ring around the fuel intake.
· Flex-fuel vehicle engines are designed to run on either standard gasoline or E85. FFVs can safely use fuel containing from 10 to 85 percent ethanol as well as gasoline of any octane level.
· If you want to use a mix of E85 and regular or premium gas in your FFV, ratios of the mix are important so consult your Owner’s Manual for recommendation or a qualified mechanic or automotive specialist.
· Ethanol burns cleaner than gasoline, which means flex-fuel cars pump fewer toxic fumes into the environment.
· Although E85 is cheaper than regular gasoline, it gets about 25% fewer miles to the gallon, so you end up buying more gas more often.
While experts continue to disagree about gasoline grades and flex-fuels, you can’t go wrong with sticking to the recommendation of the best fuel grade for your car that’s in the Owner’s Manual. The correct fuel will provide the peace of mind that you’re doing the right thing for your car while avoiding potential damage to the engine and expensive repairs.