dRAMbuie
Senior Member
- Joined
- Apr 28, 2014
- Posts
- 267
- Reaction score
- 84
- Location
- Sarnia, Ontario
- Ram Year
- 2024
- Engine
- 5.7L Hemi
First off, this information is based on my experience in the Canadian market.
I don’t know how this relates to U.S. regulations, but I’m guessing you’ll eventually go the same route south of the border - if you haven’t already.
I should also mention that I only ever fill my truck with premium fuel (91 or 92 octane).
Those who use regular will obviously have different experiences.
About 6 months ago I noticed a sudden drop in fuel mileage in my truck. By about 1.5mpg on average.
After some experimenting and doing a little research, I've figured out it is the ethanol content in my fuel that is causing the issue.
All regular and mid-grade fuel (87 to 90 octane) sold in Canada contains ethanol. However premium fuel (91 or 92 octane) has historically not contained any.
This has been changing slowly over the last few years. Almost all premium fuel sold in Canada now contains ethanol as well.
The only exception I’m aware of is Shell 91 octane. ALL super premium (94 octane) contains ethanol.
If I fill up at a Shell station I average 18mpg combined. If I fill up anywhere else I average much less.
At some stations I end up as low as 16.5mpg combined. That’s a pretty significant difference.
Even if you fill up with regular fuel, you may want to keep an eye on your mileage over the next couple of years.
Refiners have been quietly increasing ethanol content behind the scenes, and most people even don't realize it. In fact if you do a little research, you'll notice that most fuel providers no longer list their ethanol content for each fuel grade.
The fact is, that while ethanol content in gasoline is purported to burn "cleaner", it actually burns less efficiently which results in reduced fuel mileage.
Some jurisdictions legislate there be a “minimum annual average” percentage of ethanol in gasoline sold (all facilities combined). And although there is a general quality standard, the law does not dictate a maximum percentage allowable.
Why is this troubling?
Ethanol is a cheap way to increase octane. As a result, most refiners are now greatly exceeding the 5% requirement because it represents a cost savings for them.
In fact, most fuel suppliers are currently posting a 10% ethanol blend, with some organizations pushing for an increase to 20%.
Newer engines are designed to handle some ethanol content.
There is some debate about this, but generally you’re looking at about 15% before damage to valves and valve seats can occur (of course this doesn't include E85 engines).
Older engines and small engines (lawnmowers etc.) are typically not designed for any ethanol content. Unfortunately there appear to be very few options left in these cases.
For now I'll keep on using Shell 91 octane in my truck, and maybe even in my lawnmower too.
*Note - When I'm in the States, I find I get decent mileage with BP fuel. Not quite as good as Shell, but close. Haven't done any research on their products yet.
I don’t know how this relates to U.S. regulations, but I’m guessing you’ll eventually go the same route south of the border - if you haven’t already.
I should also mention that I only ever fill my truck with premium fuel (91 or 92 octane).
Those who use regular will obviously have different experiences.
About 6 months ago I noticed a sudden drop in fuel mileage in my truck. By about 1.5mpg on average.
After some experimenting and doing a little research, I've figured out it is the ethanol content in my fuel that is causing the issue.
All regular and mid-grade fuel (87 to 90 octane) sold in Canada contains ethanol. However premium fuel (91 or 92 octane) has historically not contained any.
This has been changing slowly over the last few years. Almost all premium fuel sold in Canada now contains ethanol as well.
The only exception I’m aware of is Shell 91 octane. ALL super premium (94 octane) contains ethanol.
If I fill up at a Shell station I average 18mpg combined. If I fill up anywhere else I average much less.
At some stations I end up as low as 16.5mpg combined. That’s a pretty significant difference.
Even if you fill up with regular fuel, you may want to keep an eye on your mileage over the next couple of years.
Refiners have been quietly increasing ethanol content behind the scenes, and most people even don't realize it. In fact if you do a little research, you'll notice that most fuel providers no longer list their ethanol content for each fuel grade.
The fact is, that while ethanol content in gasoline is purported to burn "cleaner", it actually burns less efficiently which results in reduced fuel mileage.
Some jurisdictions legislate there be a “minimum annual average” percentage of ethanol in gasoline sold (all facilities combined). And although there is a general quality standard, the law does not dictate a maximum percentage allowable.
Why is this troubling?
Ethanol is a cheap way to increase octane. As a result, most refiners are now greatly exceeding the 5% requirement because it represents a cost savings for them.
In fact, most fuel suppliers are currently posting a 10% ethanol blend, with some organizations pushing for an increase to 20%.
Newer engines are designed to handle some ethanol content.
There is some debate about this, but generally you’re looking at about 15% before damage to valves and valve seats can occur (of course this doesn't include E85 engines).
Older engines and small engines (lawnmowers etc.) are typically not designed for any ethanol content. Unfortunately there appear to be very few options left in these cases.
For now I'll keep on using Shell 91 octane in my truck, and maybe even in my lawnmower too.
*Note - When I'm in the States, I find I get decent mileage with BP fuel. Not quite as good as Shell, but close. Haven't done any research on their products yet.
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