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Types Of Fuel A Chevy Suburban Uses (Explained)

Types Of Fuel A Chevy Suburban Uses (Explained)

Chevrolet Suburban was introduced back in 1935 and ever since has been a part of the American SUV and off-road culture.

We’ve written extensively about these cars and the various questions you might have about them, whether that’s the exact bolt pattern of the Chevy Suburban or the various issues you might stumble across along the way.

Today we will take a look at the fuel consumption behavior of this vehicle. We will consider the 9th generation onwards since these are the ones that are still on the road in a substantial quantity.

So, what types of fuel a Chevy Suburban needs?

2020-Present-day Chevrolet Suburban with 5.3 and 6.2-liter engines are designed to work with high-quality unleaded regular gasoline, minimum 87 octane, and premium 93 rated-octane, respectively. The same holds for the 11th, 10th, and 9th generation 5.3 and 6.2-liter V8 engines. The 8.1-liter V8 engine of the 9th generation also has 87 or higher (preferred) octane.

This looks all good but doesn’t say much about the fuel efficiency of the Chevrolet Suburban. To find out more on the subject, we have taken the time to go through the specs and fuel economy numbers for all the Chevrolet Suburbans from 2000 to 2021.

Read ahead to find out for yourself how good or bad the Suburbans are for one’s pocket in terms of MPG.

Infographic explaining the different fuel types for a Chevrolet Suburban.

Fuel Requirements Based On Engine Type

2020 – Present

The current generation of the Chevrolet Suburban is offered with a 5.3 liter V8  for the base model Suburban and a 6.2-liter V8 engine for the higher output upper-tier model. These are both gasoline engines. Additionally, Chevrolet also sells Suburban with a Duramax TurboDiesel with a 3.0-liter engine size.

For the 5.3 and 6.2 liter V8 ECOTEC3 engines, Chevrolet suggests a minimum octane rating of 87 for the gasoline that is to be used for these engines. If drivers find it available, Chevrolet recommends 93-grade octane in the owner’s manual for the Chevrolet Suburban since using 93 grade will bear better engine performance and longevity.

The third variant in the Chevrolet Suburban lineup is the Duramax 3.0-liter TurboDiesel. Chevrolet suggests 1-D for regular climates or a blend of 1-D and 2-D for colder regions. They also mention that using 1-D may reduce fuel economy.

EngineRecommended fuel type
5.3 liter ECOTEC3 V887-grade octane minimum
6.2 liter ECOTEC3 V8Premium with 93 rated octane
3.0 liter Duramax TurboDiesel1-D or a blend of 1-D and 2-D, Ultra-Low Sulfur Diesel, no more than 15ppm

2014 – 2020

The 11th generation of Chevrolet Suburban was offered between 2014 and 2020. There were only two engine variants available with the 11th generation. The base models got a 5.3-liter ECOTEC3 V8 engine, and the upper-tier variants received a 6.2 liter ECOTEC3 V8 variant.

Chevrolet suggests the use of a minimum of 87-grade octane gasoline for these engines. They further suggest not to use gasoline with less than an 87-grade octane rating. With that being said, Chevrolet also states that the recommended octane rating should be at least 93 so that your engine performs better and lives longer.

EngineRecommended fuel type
5.3 liter ECOTEC3 V887-grade octane minimum
6.2 liter ECOTEC3 V8Premium with 93 rated octane

2006 – 2013

During 2006 and 2013, Chevrolet Suburban’s 10th generation was on sale. It was offered with a 5.3-liter gasoline engine. The other option was a 6.0-liter natural gas engine. Still, since we are discussing gasoline engines, we will have to stay confined to the 5.3-liter V8 engine to discuss the 10th generation Chevrolet Suburban.

This 5.3 liter V8 was standard all across the Suburban lineup. Chevrolet recommends using gasoline with a minimum octane rating of 87. They warn that using less 87-grade octane might cause engine knocking, although there may be no harm to the engine itself. They further suggest that using higher grades of octane would be better for the engine life and performance.

EngineRecommended fuel type
5.3-liter V8 engine87-grade octane minimum

1999 – 2006

From the year 1999 till 2006, the 9th generation of the Chevrolet Suburban was on sale. These units were offered with three different engines. The base model was a 5.3 liter Vortec 5300 V8, then the higher end 6.0 liter Vortec 6000 V8, and finally the 8.1 liter Vortec 8100 V8.

For all of these engines, Chevrolet suggested using high-quality gasoline with an octane rating minimum of 87. For better performance, higher grade octanes could be used, but the minimum grade suggested was 87.

EngineRecommended fuel type
5.3 liter Vortec 5300 V887-grade octane minimum
6.0 liter Vortec 6000 V887-grade octane minimum
8.1 liter Vortec 8100 V8Regular 87 Octane (pump gas) or higher

What Types Of Gasoline Can And Can’t Be Used?

With the advancement in fuels and gasoline, we now have a variety of gasoline types available at the gas stations. They range from various octane grades to gasoline types that contain additives for better engine life and performance. We will look at these individually and see if they are a suitable fit for the Chevrolet Suburban’s various generations we have seen over the years.

Reformulated Gasoline

Ever since the focus on the environment became more concentrated, gasoline refining companies have brought forward greener and cleaner-burning types of gasoline. Reformulated Gasoline is one such type. It burns cleaner and greener and has less of an impact on the environment.

Chevrolet suggests the use of reformulated gasoline (RFG) for their Suburban line of trucks. This also shows that Chevrolet, as a manufacturer cares about the environment, and their engines are RFG compatible.

Gasoline/Oxygenated Blends Or E-85

E-85 gasoline is a particular type that contains 85% ethanol blended with 15% gasoline. Usually, the E-85 is used for higher output engines, but on the flip side, it also results in decreased fuel economy. It necessitates ensuring your vehicle is E-85 compatible or not as a first step.

Manufacturers mark their vehicles with different signs and emblems so that the vehicle owners would know if their cars are E-85 compatible or not. It is essential to know since mixing E-85 with regular gasoline might cause performance issues. For instance, in colder climates, the vehicle might not start if E-85 is used in a car that is not compatible.

The signs around the vehicle to look for to determine if your car is, in fact, E-85 compatible or not. These signs are the FlexFuel badge or the clear marking of E-85 compatibility on the gas tank cap.

There are a few precautions that need to be taken when using E-85 gasoline. These are:

  • Add at least 11 liters of E-85 gasoline at the time of fill-up
  • Keep the vehicle running for at least a distance of 7 miles

Even with these measures taken, there could be some symptoms you will notice, which are:

  • Hard starting and rough idling
  • Deposit formation inside the engine, residue build-up

Due to these reasons, Chevrolet suggests that if the vehicle owners want to use ethanol added gasoline, it should be no more than 15% ethanol mixed with 85% gasoline. This, according to Chevrolet, is the safe range for the use of ethanol added gasoline.

Gasoline With Added Materials

Gasoline can play quite some part in keeping your engine safe and maintaining it. This becomes why some gasoline suppliers add chemicals like detergents, anti-corrosion, and cleaning agents with their gasoline. These can benefit your engine in both performance and life.

Chevrolet recommends Top Tier Detergent gasoline as safe to use in their engines.

Gasoline With MMT

Methylcyclopentadienyl manganese tricarbonyl (MMT) is blended with gasoline due to its octane-enhancing characteristics. This was initially sold as a supplement for use in leaded gasoline and later was sold as an octane enhancer.

Chevrolet suggests against the use of gasoline with MMT. They do so because gasoline with MMT is known for causing emissions system performance issues. Furthermore, gasoline with MMT can also cause the spark plugs to die faster than usual, which is an added expense in the vehicle’s running cost.


Biodiesel is a nature-friendly type of diesel gasoline that is most of the time sourced from soybean oil. These can also be sourced from yellow grease and canola oil, but the primary source is soybean oil. This has been used by a lot of diesel engines throughout its life.

Chevrolet suggests that biodiesel is safe to use for their Duramax TurboDiesel engine. However, they indicate that the blend shouldn’t be more than 20% biodiesel.

What If I Hear A Knocking Noise From The Engine After Refilling

Knocking sound from the engine is what all vehicle owners dislike. It is usually caused by the use of gasoline with an octane rating lower than 87. This is also known as spark knock as it is the spark plugs that cause this knocking sound due to less efficient gasoline.

Chevrolet states clearly in their manuals that if a vehicle is filled with gasoline with an octane rating lower than 87, it is highly likely that such knocking sounds can be heard from the engine. An easy fix to this problem is to use gasoline with an octane rating of higher than 87. This will cause the knocking sound to go away.

However, if the knocking sound is still there even after higher grade gasoline is used, then it is certainly time to get the engine serviced immediately.

For more insight into engine knocking check this video:

Does The Chevy Suburban Have Good Gas Mileage?

When we talk about SUVs and that with bigger engine displacements, it is pretty acceptable that these won’t be good on fuel economy.

With sedans, one may expect better fuel efficiency, but not with the SUVs having bigger engines. The Chevrolet Suburban is also a bigger engine SUV, and let’s see how it does on fuel economy.

2021 – Present

The claimed fuel economy for the Chevrolet Suburban, as mentioned on the Chevrolet website, is between the range of 15 MPG to 20 MPG. These are asserted numbers but looking at the data for earlier generations with similar engines. It will be safe to conclude that these numbers are somewhat accurate.

EngineLowest Combined MPGHighest Combined MPG
5.3 liter V8 and 6.2-liter V81520

2014 – 2020

According to the numbers available for the fuel efficiency of Chevrolet Suburban, the 5.3 liter V8 ECOTEC3 engine can achieve between 15 to 21 miles per gallon if run on regular gasoline. If E-85 is used, it can see a decline in fuel economy, lowering the range from 11 miles per gallon to 16 miles per gallon on a good day.

The 6.2-liter V8 engine is slightly better in the higher numbers at 23 miles per gallon but worse in the lower range at 14 MPG.

EngineLowest Combined MPGHighest Combined MPG
5.3 liter V81521
5.3 liter V8 (E-85)1116
6.2 liter V81423

2006 – 2013

The 10th generation of the Chevrolet Suburban was on sale from 2006 till 2013 with just one gasoline engine offering. It was the 5.3-liter V8 engine that could achieve 15 miles per gallon on a bad day. On a good one, it could go as high as 21 MPG. Then there were cases where owners were using ethanol blends for their Suburbans.

Using E-85 ethanol blend, it was clear the fuel economy would drop substantially, and so it did. The Chevrolet Suburban could achieve only 11 miles per gallon, on the lower side of the range, with the higher being 16 miles per gallon.

EngineLowest Combined MPGHighest Combined MPG
5.3 liter V8 (gasoline)1521
5.3 liter V8 (E-85)1116

1999 – 2006

From 1999 till 2006, Chevrolet sold the 9th generation of the Chevrolet Suburban. It was offered with three engine variants. The base model was a 5.3 liter Vortec 5300 V8. Then there was the 6.0 liter Vortec 6000 V8. And finally, the 8.1 liter Vortec 8100 V8 engine. All of these were gasoline engines.

The fuel consumption range for the 5.3-liter variant was between 14 and 18 miles per gallon of regular gasoline was used. There were cases where E-85 was used in the same engine, allowing for a 9 to 16 miles per gallon fuel economy range. The 6.0-liter V8 engine was a very thirsty one ranging from 12 to 16 miles per gallon.

The fuel economy data for the 8.1-liter V8 suggests that it was the worst fuel economy. Drivers experienced a very disappointingly low number of 7 miles per gallon on a bad day and 14 miles per gallon on a good one.

EngineLowest Combined MPGHighest Combined MPG
5.3 liter V8 (gasoline)1418
5.3 liter V8 (E-85)913
6.0 liter V81216
8.1 liter V8713

What’s The Gas Tank Size Of A Chevy Suburban?

The fuel tank for the current generation of Chevrolet Suburban is at 24 gallons. All previous generations of the Chevrolet Suburban were sold with a tank capacity of 26 gallons. Now let’s see how much would it cost to fill up those tanks

How Much Does It Cost To Fill Up A Chevy Suburban

GenerationFuel tank size (Gallons)Cost (Cheapest)Cost (Most Expensive)
1999 till 200626$76.23$116.12
2006 till 201326$76.23$116.12
2014 till 202026$76.23$116.12
2021 till current (gasoline)24$70.37$107.19
2021 till current (turbodiesel)24$76.28$108.98

Closing Thoughts

We’ve covered the fuel requirements from the 9th generation to the present-day Chevrolet Suburban. The verdict?

The 5.3 and 6.2-liter engines, from 2000 to 2021, are good with regular unleaded gasoline, minimum of 87 octane, although the 6.2-liter prefers premium 93 rated-octane. And the 9th gen’s 8.1-liter V8? It’ll run on 87, but higher is better.

That’s all well and good, but it’s only half the story. What about fuel efficiency? After all, knowing your Suburban’s MPG is crucial for your wallet’s well-being. To help with that, we’ve dug into the specs and fuel economy numbers for all Chevrolet Suburbans from 2000 to 2021.

If you’re looking to switch up your wheels, we may want to check our in-depth article on “The Exact Bolt Pattern Of All Chevy” models. Essential reading if you’re considering a wheel upgrade or replacement.

Stay tuned, stay informed, and happy driving!


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