Anybody use regular or mid grade gas?
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2014 C300 4matic sport sedan
Anybody use regular or mid grade gas?
I have a 2014 c300 sport Been using premium gas since i bought the car, it now has 50,000 miles but im going to start commuting more miles to work. I use full synthetic oil om oil changes. Does anybody use regular or mid grade gas and not the premium and haven’t experienced any problems such as knocking?
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, 2023 BMW X4, 1991 190E
I have a 2015 ML350 an have always used mid grade. Car has over 60,000 miles and no issues. The computer system will adjust for the lower grade and you won't know the difference unless you are always hot rodding it.
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2014 C300 4matic sport sedan
I didnt know the computer system does that thanks for reply
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2011 C300 Sport, P1, MM, Wood, Heated FS, DIY rearview camera.
I also compared 89 vs 91 on my other cars, 94 Altima, 96 Maxima, 2000 RX300 and 2002 QX4. No difference in idle smoothness, vibration, mpg, etc. Knock sensor sends detected signal to computer to adjust timing accordingly.
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2010 C300 4MATIC........ 2011 C63 AMG.............. 2015 CLS400 4MATIC.....
There have been threads where people have been using cheaper gas and have had lots of problems. Not saying it will happen to you, but you've been here a while, you may have seen some.
Usually you get a reduction in mpg anyways so it ends up not being worth it.
Usually you get a reduction in mpg anyways so it ends up not being worth it.
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2019 S560, 2015 Honda Civic Hybrid
Interesting discussion ... I think it was Car & Driver that published a test of performance and gas mileage using different octane fuels. Though they didn't test a Mercedes I believe the general finding was that gas mileage was actually higher in some cases using lower-octane and performance often not measurably different. My understanding is that higher octane just allows the computer to tune the engine for more power when it's called for, so that if your driving style calls for it you can get additional performance from premium gas. Conversely, if you're just loafing along the computer cannot do anything to take advantage of the higher octane. In fact, it's not unlike the 'E' and 'S' setting in our cars ... if you leave it on 'E' you're already detuned most of the time anyway.
The other aspect of gasoline marketing is the majors claim to have superior additive packages for their premium fuel, in theory cleaning and protecting the engine better than lower grades. Where I live, gas stations have two tanks in the ground, one for regular and one for premium and when I fill up with mid-grade I get, in theory, an equal blend of the two. Which means I get some of the supposedly superior additive ingredients with the premium component.
The other aspect of gasoline marketing is the majors claim to have superior additive packages for their premium fuel, in theory cleaning and protecting the engine better than lower grades. Where I live, gas stations have two tanks in the ground, one for regular and one for premium and when I fill up with mid-grade I get, in theory, an equal blend of the two. Which means I get some of the supposedly superior additive ingredients with the premium component.
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I always use ethanol free 94 octane (RON + MON ) / 2) in all my vehicles that call for premium gasoline.
There is a measurable difference in engine running, performance and fuel economy compared to the very few times I have been forced to use 89 octane.
It may be less expensive to initially fuel up but the dip in fuel consumption (overall range) makes up for the difference. You'll get less KM/tank with low grade gasoline.
There is a measurable difference in engine running, performance and fuel economy compared to the very few times I have been forced to use 89 octane.
It may be less expensive to initially fuel up but the dip in fuel consumption (overall range) makes up for the difference. You'll get less KM/tank with low grade gasoline.
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From: California
Mercedes C250 Coupe
Agree with C280's first two sentences...............
Use Chevron Supreme in my coupe since purchased Summer of '14. No issues to date. 1600 mile round trip to Scottsdale, AZ calc'd out to over 35 MPG.
Ir's a classy little coupe. My better half loves it. The least this old sailor can do is provide good quality benzine.................
It's a good!!
ez
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2017 C300 Coupe
It's a known fact, even admitted by several car manufacturers, that modern car computers can adjust for regular gas. Maybe performance won't be as good, but bottom line is your engine won't break.
As for your "that's what Mercedes tells you to run" line - Mercedes also wants you to pay 300$ for a "Service A" oil change, so if you want to be a sheep that's fine, but don't cry if somebody disagrees...
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2014 C300 4matic sport sedan
Even before i started this thread i knew someone would have a smartass comment like that. Thank you to everyone else that actually contributed something to make it a discussion had more insight on personal experiences which is what i was looking for than mercedes tells you to do it and the difference in money makes me need to buy a new car, smh.
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2009 C63 AMG, 2010 C250 4Matic Sport
Okay. I'll elaborate on the comment saying to run premium.
Run premium.
The ME9.7 ECU has explicit parameters to run lower octane fuel. They are not enabled by default. This means by running a fuel grade lower than 91 AKI (95 RON), the engine will retard timing to prevent pre-detonation. Your fuel mileage is likely going in the garbage unless you do anything but rest your foot on the pedal. In that case, you're still running with timing pulled back (read: not ideal for performance, fuel econ or possibly reliability). The M272 is a fairly high compression engine for being naturally aspirated. It needs the higher octane fuel.
If you're wondering how to enable these, don't bother. It decreases the chance of predetonation signficicantly, also reduces performance, and doesn't save anything in terms of fuel costs.
They're not joking, if you didn't want to factor in the ridiculously minimal increase in fuel cost, you bought the wrong car.
Run premium.
The ME9.7 ECU has explicit parameters to run lower octane fuel. They are not enabled by default. This means by running a fuel grade lower than 91 AKI (95 RON), the engine will retard timing to prevent pre-detonation. Your fuel mileage is likely going in the garbage unless you do anything but rest your foot on the pedal. In that case, you're still running with timing pulled back (read: not ideal for performance, fuel econ or possibly reliability). The M272 is a fairly high compression engine for being naturally aspirated. It needs the higher octane fuel.
If you're wondering how to enable these, don't bother. It decreases the chance of predetonation signficicantly, also reduces performance, and doesn't save anything in terms of fuel costs.
They're not joking, if you didn't want to factor in the ridiculously minimal increase in fuel cost, you bought the wrong car.
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I'll offer my experience - no personal opinions.
I have a 2013 C250 W204 sedan. The 1.8 I-4 turbo M271 is a fairly high performance engine (111.7 HP/liter) compared to the run of the mill, but certainly no AMG.
Around town I use mid grade major brand name gasoline. On the highway I use the recommended high octane gasoline, again from a major brand.
I average 25.4 MPG on mid grade in city/suburban driving. My highway average is 30.7 MPG. I do not find fuel costs to be much of an issue because the difference in price between regular and premium comes to less than $10 per tankful. I tried a few tanks of high octane around town and found no measurable performance or mileage difference. I have not tested mid grade on the highway.
The comments about the anti detonation sensors are correct. When the engine sensor detects pre-ignition, the timing is reduced to eliminate it. For that to happen, some low level detonation has to occur first.
2 of my indie mechanic friends have told me to stay out of the engineering menu where the fuel characteristics can be set because I won't like the results.
I have spoken with persons in the automotive fuel industry and their professional opinion is that the biggest difference in fuel grades (aside from the octane) for modern cars comes in the additive packages. The regular and mid grade blends often contain less of the "detergents" that help to minimize deposits. The discount brands may also contain less. They say that detergent additives become less of an issue with direct injection engines.
I'm going to continue doing what I'm doing because it has caused no issues in 4 MBs in about 550,000 miles of driving.
I have a 2013 C250 W204 sedan. The 1.8 I-4 turbo M271 is a fairly high performance engine (111.7 HP/liter) compared to the run of the mill, but certainly no AMG.
Around town I use mid grade major brand name gasoline. On the highway I use the recommended high octane gasoline, again from a major brand.
I average 25.4 MPG on mid grade in city/suburban driving. My highway average is 30.7 MPG. I do not find fuel costs to be much of an issue because the difference in price between regular and premium comes to less than $10 per tankful. I tried a few tanks of high octane around town and found no measurable performance or mileage difference. I have not tested mid grade on the highway.
The comments about the anti detonation sensors are correct. When the engine sensor detects pre-ignition, the timing is reduced to eliminate it. For that to happen, some low level detonation has to occur first.
2 of my indie mechanic friends have told me to stay out of the engineering menu where the fuel characteristics can be set because I won't like the results.
I have spoken with persons in the automotive fuel industry and their professional opinion is that the biggest difference in fuel grades (aside from the octane) for modern cars comes in the additive packages. The regular and mid grade blends often contain less of the "detergents" that help to minimize deposits. The discount brands may also contain less. They say that detergent additives become less of an issue with direct injection engines.
I'm going to continue doing what I'm doing because it has caused no issues in 4 MBs in about 550,000 miles of driving.
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Why are you getting offended by somebody else's gas preference? You need to get a life if this frustrates you.
It's a known fact, even admitted by several car manufacturers, that modern car computers can adjust for regular gas. Maybe performance won't be as good, but bottom line is your engine won't break.
As for your "that's what Mercedes tells you to run" line - Mercedes also wants you to pay 300$ for a "Service A" oil change, so if you want to be a sheep that's fine, but don't cry if somebody disagrees...
It's a known fact, even admitted by several car manufacturers, that modern car computers can adjust for regular gas. Maybe performance won't be as good, but bottom line is your engine won't break.
As for your "that's what Mercedes tells you to run" line - Mercedes also wants you to pay 300$ for a "Service A" oil change, so if you want to be a sheep that's fine, but don't cry if somebody disagrees...
As far as your comment about the $300 Service A that is not relevant to this conversation as a Service A at a MB Dealer vs a MB Shop is the same because the checks and service carried about are written specifically in the service book. The cheaper price comes from the fact that the MB Shop has a lower overhead cost vs the dealer.
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2017 C300 Coupe
Oh boy here we go... Someone who is annoyed I confronted the white elephant in the room. No one here is frustrated and I couldn't care less what you run as it is your car and you would have to live with it. However, when you post a question about what fuel to run in your car you are now asking for the input of others. Basically the owners manual tells you what to run. MB has engineers who design and build the cars to run the way they should and using the premium fuel does that. No your engine will not explode but overtime it puts unneeded wear and tear on the engine from not running the proper fuel. Also, try making a warranty claim on a engine that is not running correct fuel. The performance of the car suffers as does the MPG. All of this was my reason behind my comment "Thats what Mercedes tells you to run"
As far as your comment about the $300 Service A that is not relevant to this conversation as a Service A at a MB Dealer vs a MB Shop is the same because the checks and service carried about are written specifically in the service book. The cheaper price comes from the fact that the MB Shop has a lower overhead cost vs the dealer.
As far as your comment about the $300 Service A that is not relevant to this conversation as a Service A at a MB Dealer vs a MB Shop is the same because the checks and service carried about are written specifically in the service book. The cheaper price comes from the fact that the MB Shop has a lower overhead cost vs the dealer.
Like who are you to tell someone they have the wrong car? Why is it any of your business? Just give your view i.e. "Yes premium is better for the health of the vehicle as well as for warranty claims", and leave the attitude behind.
And by the way, I personally use premium gas but I have used my warranty even when I used to use regular gas. This was never checked out by the dealer, so I don't think this should be a concern.
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2014 C300 4matic sport sedan
Lol don't tell me you couldn't care less when you write bs like "If the extra $15 makes a difference in your life then you need to buy a new car..."
Like who are you to tell someone they have the wrong car? Why is it any of your business? Just give your view i.e. "Yes premium is better for the health of the vehicle as well as for warranty claims", and leave the attitude behind.
And by the way, I personally use premium gas but I have used my warranty even when I used to use regular gas. This was never checked out by the dealer, so I don't think this should be a concern.
Like who are you to tell someone they have the wrong car? Why is it any of your business? Just give your view i.e. "Yes premium is better for the health of the vehicle as well as for warranty claims", and leave the attitude behind.
And by the way, I personally use premium gas but I have used my warranty even when I used to use regular gas. This was never checked out by the dealer, so I don't think this should be a concern.
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Lol don't tell me you couldn't care less when you write bs like "If the extra $15 makes a difference in your life then you need to buy a new car..."
Like who are you to tell someone they have the wrong car? Why is it any of your business? Just give your view i.e. "Yes premium is better for the health of the vehicle as well as for warranty claims", and leave the attitude behind.
And by the way, I personally use premium gas but I have used my warranty even when I used to use regular gas. This was never checked out by the dealer, so I don't think this should be a concern.
Like who are you to tell someone they have the wrong car? Why is it any of your business? Just give your view i.e. "Yes premium is better for the health of the vehicle as well as for warranty claims", and leave the attitude behind.
And by the way, I personally use premium gas but I have used my warranty even when I used to use regular gas. This was never checked out by the dealer, so I don't think this should be a concern.
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Read my statement...
Good luck claiming a engine issue for your warranty when you do not use the proper fuel. Same goes for oil or filters and other fluids as well. When a car is under warranty and something goes wrong MB is not going to just pay out for say a major repair like a engine issue costing potentally thousands of dollars. They will investigate first and it has happened to not just MB but other makes I am sure as well. People use non OEM parts, wrong fuel or oil ,ect and MB does not cover the repair. That is what I was saying.
Good luck claiming a engine issue for your warranty when you do not use the proper fuel. Same goes for oil or filters and other fluids as well. When a car is under warranty and something goes wrong MB is not going to just pay out for say a major repair like a engine issue costing potentally thousands of dollars. They will investigate first and it has happened to not just MB but other makes I am sure as well. People use non OEM parts, wrong fuel or oil ,ect and MB does not cover the repair. That is what I was saying.
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Laxpower, in answer to your question, I run mid-range in my car. I live in a very slow, congested central city area and rarely get my Mercedes above 2,000 rpm for any sustained period. My warranty expired in January, so the kind of gas I use and the way I drive will never matter to anyone but myself. For the way I use this car, I do not feel a need for higher octane fuel.
My Porsche is an entirely different story ... I love opening it up on the highway and going to club events at the coast or the hill country. It definitely runs better on premium and that's all I use in that car.
My Porsche is an entirely different story ... I love opening it up on the highway and going to club events at the coast or the hill country. It definitely runs better on premium and that's all I use in that car.
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Laxpower, in answer to your question, I run mid-range in my car. I live in a very slow, congested central city area and rarely get my Mercedes above 2,000 rpm for any sustained period. My warranty expired in January, so the kind of gas I use and the way I drive will never matter to anyone but myself. For the way I use this car, I do not feel a need for higher octane fuel.
My Porsche is an entirely different story ... I love opening it up on the highway and going to club events at the coast or the hill country. It definitely runs better on premium and that's all I use in that car.
My Porsche is an entirely different story ... I love opening it up on the highway and going to club events at the coast or the hill country. It definitely runs better on premium and that's all I use in that car.
Also, before you say you didn't notice any change in fuel mileage, your dashboard isn't entirely telling the truth on that.
