what grade gas do you guys use for C300?
Junior Member
Joined: Sep 2010
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From: NJ
Mercedes Benz C300 4matic 1967 Chevelle SS
I was not advocating otherwise. 
btw, thanks for all the fun facts but I was only questioning whether lower octance fuel burns at a slower rate (what you said), or whether it ignites at a lower temperature and also whether using higher octance fuel than recommended by the manufacturer will result in better gas mileage (which I say is not true).
btw, thanks for all the fun facts but I was only questioning whether lower octance fuel burns at a slower rate (what you said), or whether it ignites at a lower temperature and also whether using higher octance fuel than recommended by the manufacturer will result in better gas mileage (which I say is not true).I think my previous posts answers all questions; higher octane gas than the manufactuer recommends does in fact result in better MPG in some vehicles according to Car and Drivers test results with the BMW M3.
(See my above post).
(The 2001 - 2007 BMW M3 with the S54 engine is one such car. Car and Driver magazine dyno tested a car and found that the power output increased as the AKI was increased up to approximately 96 AKI. Also, these systems can result in HIGHER FUEL MILEAGE MPG for cars designed for the HIGHER OCTANE fuels.)
Last edited by 4maticbenz; Mar 23, 2011 at 08:02 PM.
Junior Member
Joined: Sep 2010
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From: NJ
Mercedes Benz C300 4matic 1967 Chevelle SS
Yes, I do know that the only difference between the gas chains are the additive packages... That is what I said in my post. Which is why I have recommended every couple thousand miles to switch the brand of gasoline. I have read many reports and talked with people familiar to the subject. After a while (thousands of miles on the same gas), the additives themselves start to build up, so it would be best to switch the gas brand to get some different additives in to take care of buildup that not only that particular additive can't remove, but also to help remove buildup of the first additive.
While Porsche does reccomend fuel additives like Techron, Mercedes Doesn't. Soemthing to do about having an adverse effect elsewhere along the chain and drying out some lines. But I'm no expert...
While Porsche does reccomend fuel additives like Techron, Mercedes Doesn't. Soemthing to do about having an adverse effect elsewhere along the chain and drying out some lines. But I'm no expert...
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From: MA
'24 Porsche Macan
I think my previous posts answers all questions; higher octane gas than the manufactuer recommends does in fact result in better MPG in some vehicles according to Car and Drivers test results with the BMW M3.
(See my above post).
(The 2001 - 2007 BMW M3 with the S54 engine is one such car. Car and Driver magazine dyno tested a car and found that the power output increased as the AKI was increased up to approximately 96 AKI. Also, these systems can result in HIGHER FUEL MILEAGE MPG for cars designed for the HIGHER OCTANE fuels.)
(See my above post).
(The 2001 - 2007 BMW M3 with the S54 engine is one such car. Car and Driver magazine dyno tested a car and found that the power output increased as the AKI was increased up to approximately 96 AKI. Also, these systems can result in HIGHER FUEL MILEAGE MPG for cars designed for the HIGHER OCTANE fuels.)
Junior Member
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From: NJ
Mercedes Benz C300 4matic 1967 Chevelle SS
In a previous post, I said that you said that lower octane fuel burns at a slower rate. I was incorrect. You said that's the case for higher octane fuel. I did find some references that indicated that was true. However, most references I found said that using a higher octane fuel than recommended by the manufacturer was a waste of money and did not increase gas mileage.
Usually using a higher octane fuel than recommended by the OEM will not result in higher MPG, but in a few vehicles, esp. high performance ones, it will.
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From: Dix Hills, New York
2012 C250 Coupe
MBWorld Fanatic!
Joined: Sep 2009
Posts: 2,108
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From: Dix Hills, New York
2012 C250 Coupe
Well, it was at a sunergy place (never really heard of them) but its the only station I have found on Long Island that carries E85... The prices here greatly vary. The average price is 3.75 for regular, 4.00 for premium 93 from the popular chains. But then you will find those crazy shell stations that are charging 4.00 for regular and near 4.35 for premium!
I have managed to find a Sunoco station near work that is 3.85 for premium 93 octane, and same price for credit!
I have managed to find a Sunoco station near work that is 3.85 for premium 93 octane, and same price for credit!
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Joined: Dec 2012
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C300
I've been filling my 2009 C300 up with 87 for the past 10000 miles (mostly highway). Can easily get a mileage of 28 on the highway. Noticed no knocking or performance issues. Never tried E85 though - am curious about it.
Senior Member
Joined: Mar 2012
Posts: 455
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From: Lancaster, PA
2010 E350
Never less than 93 octane for me. 87 made my car knock and ping when I first drove it off the dealer lot, they put crappy 87 in it and said it was fine but the inside of the filler door says no less than 91
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Joined: Oct 2011
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From: NOVA
c300 4matic
+1 I used 87 a few times and my car ping. switched to 93 and thats what I've been using ever since.
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2010 C-300
Your fuel mileage will go down significantly with E85. You realize that the 85 in E85 is not the octane rating, but it's the percent ethanol right? It has much lower BTU's and therefore a less efficient burn and thus lower fuel economy...the Octane of E85 is alot higher, but because of the lower economy, it has to be quite a bit cheaper than Premium gas to be a sensible purchase.
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2010 C300
A perfect example of how car salesman know little to nothing about cars in general. 'once a month' is going to do nothing for your car, MB tunes the motors so that they require a little higher octane - that is how they get better performance numbers out of their motors. It isn't because it is a "premium car" and premium fuel has nothing to do with longevity of your engine or how clean it burns or anything else of that nature. It is purely the way the motor was tuned, likely unnecessarily considering these engines aren't high compression as far as I know lol.
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2011 C300
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c300
Hi,
Purchased 2013 c 300 a week back.
My dealer told me to use 85 normal gas. he said new engines are designed to handle the normal gas.
Is it true ?
On the inside of my gas filler door, it tells me that I can use E85 in this car..
Purchased 2013 c 300 a week back.
My dealer told me to use 85 normal gas. he said new engines are designed to handle the normal gas.
Is it true ?
On the inside of my gas filler door, it tells me that I can use E85 in this car..
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Joined: Sep 2009
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From: Dix Hills, New York
2012 C250 Coupe
Typically on E85 you may receive less fuel economy, but the lower cost usually outweighs the cons of fuel economy resulting in net savings. Fuel systems and lines need to be designed to support E85 and should only be used in cars that specify they can support it on the fuel door (which you said your door states it can).
As far as regular gas goes, Mercedes engines are designed for premium 91 octane minimum (most premium gas at stations is 93 octane). However, the engines have knock sensors which can detect premature detonation (due to lower octane) and Adjust timing, etc to prevent engine knock or damage to the engine. I would recommend sticking with 93 octane regular gas for best performance and fuel economy, but you should definitely try out e85 if your car can support it and see how you like it.
It's not recommended to mix the two, so that is a disadvantage for e85 gas as not many stations (at least in northeast region) carry it. You should try to let your fuel tank run as low as possible before switching from e85 to regular pump gas (and vice versa).
Hope this helps.
Last edited by jctevere; Jun 22, 2015 at 11:45 AM.
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2011 C300
I always use premium gas. 91 where I live!
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c300
I believe only non 4matic w204s in certain years can handle E85 gas blends (which is NOT normal gas). It means 85% ethanol and 15% regular gas. It is considerably cheaper than regular 87 octane gas (which is 10% or less ethanol and 87 percent isooctane).
Typically on E85 you may receive less fuel economy, but the lower cost usually outweighs the cons of fuel economy resulting in net savings. Fuel systems and lines need to be designed to support E85 and should only be used in cars that specify they can support it on the fuel door (which you said your door states it can).
As far as regular gas goes, Mercedes engines are designed for premium 91 octane minimum (most premium gas at stations is 93 octane). However, the engines have knock sensors which can detect premature detonation (due to lower octane) and Adjust timing, etc to prevent engine knock or damage to the engine. I would recommend sticking with 93 octane regular gas for best performance and fuel economy, but you should definitely try out e85 if your car can support it and see how you like it.
It's not recommended to mix the two, so that is a disadvantage for e85 gas as not many stations (at least in northeast region) carry it. You should try to let your fuel tank run as low as possible before switching from e85 to regular pump gas (and vice versa).
Hope this helps.
Typically on E85 you may receive less fuel economy, but the lower cost usually outweighs the cons of fuel economy resulting in net savings. Fuel systems and lines need to be designed to support E85 and should only be used in cars that specify they can support it on the fuel door (which you said your door states it can).
As far as regular gas goes, Mercedes engines are designed for premium 91 octane minimum (most premium gas at stations is 93 octane). However, the engines have knock sensors which can detect premature detonation (due to lower octane) and Adjust timing, etc to prevent engine knock or damage to the engine. I would recommend sticking with 93 octane regular gas for best performance and fuel economy, but you should definitely try out e85 if your car can support it and see how you like it.
It's not recommended to mix the two, so that is a disadvantage for e85 gas as not many stations (at least in northeast region) carry it. You should try to let your fuel tank run as low as possible before switching from e85 to regular pump gas (and vice versa).
Hope this helps.
Thank you.
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2016 GLE450 AMG Coupe
Member
Joined: Jan 2013
Posts: 146
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2013 c350 Coupe
Agreed - we knew what we got ourselves into when purchasing these vehicles. You could debate the wording if they said "recommended" 91, but if I recall correctly, when I open my gas door it says MIN 91. The $2-$4 savings is negligible on the spot, but the risk of incurring a few hundred or thousand dollars in repairs is not worth it. We purchased these cars for their looks, their features and certainly their performance - fuel them up properly!
Member
Joined: Oct 2014
Posts: 156
Likes: 6
From: Pennsylvania, USA
2014 C300 Luxury
I believe only non 4matic w204s in certain years can handle E85 gas blends (which is NOT normal gas). It means 85% ethanol and 15% regular gas. It is considerably cheaper than regular 87 octane gas (which is 10% or less ethanol and 87 percent isooctane).
Typically on E85 you may receive less fuel economy, but the lower cost usually outweighs the cons of fuel economy resulting in net savings. Fuel systems and lines need to be designed to support E85 and should only be used in cars that specify they can support it on the fuel door (which you said your door states it can).
As far as regular gas goes, Mercedes engines are designed for premium 91 octane minimum (most premium gas at stations is 93 octane). However, the engines have knock sensors which can detect premature detonation (due to lower octane) and Adjust timing, etc to prevent engine knock or damage to the engine. I would recommend sticking with 93 octane regular gas for best performance and fuel economy, but you should definitely try out e85 if your car can support it and see how you like it.
It's not recommended to mix the two, so that is a disadvantage for e85 gas as not many stations (at least in northeast region) carry it. You should try to let your fuel tank run as low as possible before switching from e85 to regular pump gas (and vice versa).
Hope this helps.
Typically on E85 you may receive less fuel economy, but the lower cost usually outweighs the cons of fuel economy resulting in net savings. Fuel systems and lines need to be designed to support E85 and should only be used in cars that specify they can support it on the fuel door (which you said your door states it can).
As far as regular gas goes, Mercedes engines are designed for premium 91 octane minimum (most premium gas at stations is 93 octane). However, the engines have knock sensors which can detect premature detonation (due to lower octane) and Adjust timing, etc to prevent engine knock or damage to the engine. I would recommend sticking with 93 octane regular gas for best performance and fuel economy, but you should definitely try out e85 if your car can support it and see how you like it.
It's not recommended to mix the two, so that is a disadvantage for e85 gas as not many stations (at least in northeast region) carry it. You should try to let your fuel tank run as low as possible before switching from e85 to regular pump gas (and vice versa).
Hope this helps.
That being said, you are not correct on the mixing. The car is designed to run on pure E85, 91+ Octane, or any combination of the two.
I haven't yet used E85 as the price is higher than 93 Octane here and it is less powerful... But if you have a Flex Fuel W204 you can use it in any combination you want. According to Mercedes...
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c300 4matic
what a dick response
I give you a clue.
What do you think we think of you for asking a question that already has been posted on MBWorld numerous times without searching for an answer first?
You are #1. Thats what we think of you.
What do you think we think of you for asking a question that already has been posted on MBWorld numerous times without searching for an answer first?
You are #1. Thats what we think of you.
