We’ve talked extensively about the Mazda CX-5 and various questions you may have about this particular SUV. However, we haven’t yet talked about the fuel requirements of this particular car. Therefore, we’ll do that today. Let’s start with a quick answer:
All generations of the Mazda CX-5 manufactured between 2012 – Present-day that have a gasoline engine use regular, unleaded gasoline with an octane rating of 87. Diesel engines use Ultra-Low Sulfur Diesel with 15 ppm sulfur or less that meets the ASTM D975 standard.
However, that certainly doesn’t tell the whole story. There’s various variants of gasoline and diesel that you’ll come across at gas stations and all of them have a different compatibility with the CX-5. We’ll discuss these kinds of fuel in detail to give you as clear of an image as possible. Finally, we’ll discuss the gas tank size of the CX-5. Read on!
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Premium Gasoline
Let’s first talk about the use of premium and regular gasoline in the Mazda CX-5. This is because many people believe that premium gasoline should be used regardless of what the owner’s manual says. Premium gasoline has an octane rating of 91 or higher, and it’s supposed to increase the car’s performance and prolong the lifespan of the engine.
However, we advise you to stick with regular unleaded gasoline with an octane rating of 87 for the CX-5. The reason for this is that premium gasoline will not have any benefits for this particular car. Yes, the car will have no problem running on premium gasoline. However, you’ll not see any performance benefits or reduced maintenance costs. This is because only engines that are designed to make use of premium gasoline can receive benefits from it.
Because premium gasoline also costs more than regular gasoline, it’s best to stick with the recommendations of Mazda.
Also read: The Complete Cost Of Maintaining A Mazda
Reformulated Gasoline
The use of reformulated gasoline is essential to discuss because this particular kind of gasoline is becoming more and more common in the United States. Reformulated gasoline is the gasoline that’s designed to burn cleaner and therefore has fewer emissions than non-reformulated gasoline. This kind of gasoline was first introduced in California about two decades ago and has since become mandatory in 19 areas of the United States.
However, is the Mazda CX-5 compatible with this kind of gasoline? The answer to that is yes. The CX-5 is accepting of reformulated gasoline. Furthermore, reformulated gasoline is advised by Mazda whenever you have the chance to use it. This is because it costs the same as non-reformulated gasoline, it delivers the same performance, and causes the same wear-and-tear. Therefore there are no disadvantages to this kind of gasoline.
Also read: The Expected Mileage Of A Mazda CX-5
Oxygenated Blends
Another topic we need to discuss is the use of oxygenated blends of gasoline.This is because oxygenated blends of gasoline are standard at gas stations, but they can’t be used without some precautions. Let’s first discuss why you would want to use oxygenated blends and what they are.
Oxygenated blends of gasoline are blends that contain a certain percentage of ethanol or methanol. These chemicals are common in colder areas because it makes it easier for cars to start. However, not all engines are optimized for use with ethanol or methanol, and using this form of fuel in too high of a percentage can result in severe damage to the engine and the fuel system.
For methanol, the rule is that you cannot use any gasoline that contains methanol in the CX-5. Doing so will result in damage immediately. Ethanol can be used, but only a maximum of 10% ethanol is allowed in the fuel. Therefore E-10 is allowed but E-15 and E-85 are not. Especially E-85, which contains 85% ethanol, will cause significant damage.
Also read: The Exact Bolt Pattern Of A Mazda CX-5
Gasoline With Additives
The use of additives in the fuel of the Mazda CX-5 is also an essential point of discussion. These days, many aftermarket additives are available that supposedly help your CX-5 get the most out of the fuel. Examples of this are additives that clean your engine or so-called octane boosters.
Mazda recommends against the use of aftermarket additives that Mazda themselves doesn’t sell. Also, don’t get it twisted: this is not a marketing trick. The reason why they advise against these additives is because some of them will contain harmful materials such as silicone or metallics that will severely damage the engine and fuel system when used with your CX-5.
Instead, Mazda advises you to only use additives that are sold by Mazda themselves. However, we would generally also advise against doing this. The reason for this is that additives usually don’t have any benefit for the car. Instead, we would advise you to buy fuel that’s sold by certified TOP TIER retailers.
Fuel that’s sold by TOP TIER retailers meets all the safety requirements of fuel, and it contains all the suitable additives that are already mixed into the fuel itself. This will save you money and guarantee you that the engine stays in peak condition. You can find a TOP TIER retailer via toptiergas.com.
Diesel Requirements
All generations of the Mazda CX-5 also have a diesel engine. The diesel engines of the CX-5 use Ultra Low Sulfur Diesel with 15 ppm or less. Furthermore, it’s advised to use No.2 diesel during summer and No.1 diesel when temperatures fall below freezing.
The reason for this is that there are two different kinds of diesel. They each react differently to warmer and colder temperatures. Mazda advises you to switch to other types of diesel depending on the temperature in your region. However, don’t be worried because this is true for almost all diesel vehicles, and therefore, gas stations will communicate what kind of diesel is being used.
Another essential aspect to know is that CX-5 cannot run on diesel that has more than 5% biodiesel mixed into it. This will result in severe engine damage that’s not covered under the warranty.
A final note Mazda makes about the use of diesel in the CX-5 is that it’s important not to mix up the diesel fuel and the DEF intakes of the car. DEF stands for ‘Diesel Exhaust Fluid’ and is a solution that’s sprayed into diesel fuels to break down harmful NOx emissions. However, the intake for the DEF is right next to the intake for the gas tank, as shown below. It’s important not to mix these two things up.
Knocking Noise After Refilling
Finally, it can happen that you hear a knocking noise right after refilling. Now, it’s important to know that a slight knocking noise for the CX-5 and any other car is completely normal. Especially when the car is performing under heavy stress (such as when towing or driving up a hill) it can happen that you hear a slight knocking noise. This is nothing to be worried about.
However, if the knocking noise becomes louder and it happens right after refilling, you have a problem on your hands. It’s essential to stop the car immediately and contact your dealer for assistance. You’ve likely used fuel with a lower than recommended octane rating, which causes heavy engine knock. This will result in severe damage that’s not covered under the warranty.
The car will need to be drained from the fuel, the fuel filter will need to be replaced and the memory of the car will need to be reset by disconnecting and reconnecting the battery.
Gas Tank Size Per Generation
All 2WD versions of the Mazda CX-5 have a fuel tank capacity of 14.8 gallons (56 liters), whereas all AWD versions of the CX-5 have a fuel tank capacity of 15.3 gallons (58 liters).
Sources
- https://www.mazdausa.com/siteassets/pdf/owners-optimized/2016/cx5/2016-cx-5-owners-manual.pdf
- https://www.mazdausa.com/static/manuals/2021/cx-5/contents/04040101.html?kw=octane&hw=octane
Hi! My name is Stefan; I’m the owner and lead writer at TheDriverAdviser.com.
I’m an active writer on this blog myself, as well as a novice car mechanic. For the really technical stuff, I find writers with experience as a mechanic or who have studied mechanical engineering.
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