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Can You Put E85 in a Jeep Wrangler?

Can You Put E85 in a Jeep Wrangler?

The official fuel recommendation from Jeep advises using fuel with an octane level of 87 or higher. As gas prices continue to rise, many drivers may be wondering if they can fuel their vehicles with E85 instead of standard gasoline. E85 doesn’t work with all vehicles, however, which may lead some drivers to wonder: can you put E85 in a Jeep Wrangler?

The high levels of ethanol in E85 can cause damage to the rubber hoses of a Jeep Wrangler, or any other standard-gas-operated vehicle. While putting E85 in the fuel tank will not immediately ruin the car, extended use of E85 flex-fuel can cause long-term damage to the hoses and engine block.

As a general rule, don’t fill your vehicle with E85 flex-fuel unless your owner’s manual specifies that the vehicle has been designed to handle it. Keep reading to learn more about E85 and what is required before a Jeep Wrangler can run on it.

Flex-Fuel Systems for Jeep Wranglers

According to American Muscle, adapting a vehicle to run on E85 may require an update of the entire fueling system, as E85 has a lower level of potential energy than standard gasoline. If the fueling system is adequately adapted, however, E85 can provide a safer fuel for high octane performance, reducing the risk of combustion and overheating.

One example of a flex-fuel system created specifically for the Jeep Wrangler is the ProFlex Commander. Modifying your Jeep Wrangler to alternate between gas and ethanol can be beneficial to the engine performance for offroad conditions.

Burning E85 allows the engine to run cooler while still providing the high-intensity power Wranglers need to climb over natural off-road obstacles.

If you’re not installing a flex-fuel-specific system in your Jeep Wrangler, it’s not recommended to run the vehicle on E85 fuel. Many drivers replace rubber hoses with flexible steel lines or similar materials in order to mitigate the risk E85.

What is E85/Flex-Fuel?

Flex Fuel, officially known as Ethanol-85 (E85), is a vehicle fuel comprised of ethanol and gasoline. The percent ratio of gasoline to ethanol can vary depending on local regulation and brand variance. In order to be classified as E85, however, the mixture must have an ethanol level between 51% and 83%, according to the US Department of Energy.

E85 flex-fuel has been praised by Treehugger for being more environmentally friendly, creating lower carbon emissions than traditional fuels. Ethanol has a cooler combustion temperature than gasoline, which makes for cleaner exhaust emissions.

E85 is made mostly of processed corn, as opposed to gasoline which is reliant on fossil fuel mined from the Earth. Provided that corn processed into E85 is sustainably grown and harvested, this means that the production and consumption of flex-fuel has a lighter impact on the environment than gasoline.

Here’s a video explaining which type of fuel is best for your car, with more info below:

Is E85 Cheaper than Gasoline?

The price-per-gallon rate of E85 is typically lower than that of gasoline, which leads many to consider flex-fuel as a cost-friendly response to rising gas prices. Due to a significantly lower fuel efficiency rate, however, E85 typically ends up costing the driver more.

E85 is consumed much faster than traditional gasoline, which means that drivers have to refill the tank more often. According to Kiplinger, E85 costs an average of 1 cent more per mile than gasoline.

E85 can be a money-saving alternative for short, high-horsepower needs, but ends up costing more if used for daily commuting.

The heightened resistance of E85 makes it a more affordable alternative to race fuel if the engine has been properly built or converted for flex-fuel. Ethanol also burns cooler than gasoline, which lowers the risk of detonation.

Can Standard Vehicles Run on E85?

The ethanol to gasoline ratio of E85 gives an approximate octane of 105, which is much higher than standard gas and can be hard on the injectors, rubber components, and engine block. Higher octane levels generate resistance in the early fuel ignition, which can cause some minor damage, pinging, or knocking in the engine.

If you fill a standard vehicle with E85 flex-fuel rather than gasoline, it will still run. Car and Driver warns, however, that the check engine light may come on if the gas tank of a non-flex-fuel vehicle is filled with E85.

In the scenario that the E85 is already in the gas tank, North Short Honda recommends topping the tank off with standard gas. The risk of E85 harming to the engine is low enough that one tank, especially when diluted with standard fuel, should not generate any serious or permanent damage.

Pros and Cons of E85

If you’re deciding whether to modify your Jeep Wrangler to run on flex-fuel, it’s helpful to look at the benefits and drawbacks side by side. Here are some of the pros and cons of running on E85, according to Car and Driver.

Pros of E85

  • Lower price per gallon than gasoline
  • Lower combustion temperatures reduce the risk of detonation
  • More environmentally friendly than gasoline
  • Sustainable fuel production
  • Flex-fuel drivers are rewarded with tax benefits

Cons of E85

  • Flex-fuel crops are reliant on weather conditions
  • Possible risk of damage to the engine, if not properly modified
  • Poor gas mileage
  • Overall higher fuel cost for the driver
  • Not all gas stations sell E85

The general consensus from sources used in this article is that E85 can be a clean-burning, cost-effective alternative to high octane gasoline. This makes it useful in racing and high-speed, short-distance situations. E85 is costly and potentially harmful if used in a standard vehicle for regular commuting.

Final Thoughts

Jeep Wranglers are not traditionally built to be run on E85 fuel. There are modified fueling systems that can be installed in order to permit a regulated usage of E85, which some Jeep enthusiasts find helpful in off-roading.

The risk of using E85 in an unmodified Jeep Wrangler is the high-intensity ethanol mixture, which can cause damage to hoses and fuel injectors. The addition of a flex-fuel system to a Jeep Wrangler will not result in a lower fuel budget.

In spite of lower pump prices, E85’s poor gas mileage makes it more expensive to the driver than traditional gasoline.

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