2020 E450 Wagon?
Last edited by 2012 merc amg; Jan 19, 2020 at 02:30 AM.




My settings are:
- Steering: Sport Mode
- Engine: Eco Mode
- Handling: comfort mode
In these settings on the open road at 74 mph, I get 31 to 33 mpg. That is not "observed" but actual: take total distance and divide by gallons used, again using regular!
My settings are:
- Steering: Sport Mode
- Engine: Eco Mode
- Handling: comfort mode
In these settings on the open road at 74 mph, I get 31 to 33 mpg. That is not "observed" but actual: take total distance and divide by gallons used, again using regular!
The Best of Mercedes & AMG




Test after test have shown that there is a HP loss of between 5% and 7% when you use regular vs. premium. That means instead of 362 HP I am only getting between 335 HP adn 344 HP, more than adequate for my driving.
All modern cars have electronic "knock sensors" which take care of any "pre-detonation" that might occur using regular vs. premium.
You must have a different owner's manual than I do.
At page 411 is the following:
"If you want maximum engine output: only refuel with unleaded premium grade gasoline with an octane number of at least 91AKI/95RON
As a temporary measure, if the recommended fuel is not available, you may also refuel with unleaded regular gasoline with at least 87 AKI. 91 RON. This may reduce engine output and increase fuel consumption"
From this I take:
- For full performance premium is recommended. I have never ever used, or even come close to using the "maximum output" of my E450. I have the V6, E450 because of the smoothness and quiet vs. the 4 cyclinder, E300/350.
- You can use regular if you drive sanely - i.e., modestly which I do.
I have tested each of those cars using regular vs. premium and I have calculated no difference in average mpg.
The only real difference I have found is the extra money in my pocket!
I realize others on this Board may say if I can afford a $70,000 plus car I can afford premium gasoline.
They are of course correct - I of course can afford premium, but that is besides the point.
Each of us chooses where to spend our money, and I choose not spend it on gasoline.
Last edited by JTK44; Jan 19, 2020 at 08:10 PM.
At page 411 is the following:
"If you want maximum engine output: only refuel with unleaded premium grade gasoline with an octane number of at least 91AKI/95RON
As a temporary measure, if the recommended fuel is not available, you may also refuel with unleaded regular gasoline with at least 87 AKI. 91 RON. This may reduce engine output and increase fuel consumption"
I agree with the rest of your points, having used Regular gas in both my VW GTI and Acura RDX. It's this note that bothers me. If I have an engine failure during the warranty, and they know I've been using Regular gas (don't know how they'd know, of course), they could well point to this note as the cause of failure. I/you could lie to them, but I'm not sure I want to take that chance.




If premium was mandatory that would be a different story. But it is not.
If you tax your engine, for example flooring you engine at the stop light when it turns green, driving at altitude while towing (highly unlikely) or wanting the utmost performance, then premium is necessary.
Like you and many, many other posters, we are in our 70's, drive conservatively, and do not tax our engines.
For this type of driving regular is more than sufficient.
I am not the least bit worried about "engine failure": my driving habits do not tax the engine and in those rare cases where it might, the anti pre-detonation features of electronic ignitions will take care of any problems associated with using regular gas.
As I posted I have been using regular gas in cars that recommended (but not mandatory) premium for over 20 years with no ill effect. All had electronic ignition with anti pre-detonation that prevented any problem from using regular gasoline.




Not using premium may cause (and may not) premature engine wear - not engine failure.
If you use regular it is not recommended to drive at maximum speed, which in Germany is 150+ mph, sudden acceleration or driving above 3000 RPM which is above 110 mph.
So if you race from a stop light, intend to drive at maximum speed or drive above 110 MPH for sustained periods use premium gas!
Is this you? If so I would recommend premium: otherwise, unless you have a large position in oil companies, save your money and use regular!
To me using premium for the type of driving I do is akin to changing oil every 5,000 miles: It won't hurt but it is unnecessary and a waste of money.
BTW, do you think all the Mercedes sold in Africa, Asia, India and other third world countries are running on premium? Hardly.
These engines are designed to run or either premium or regular. That is what the electronic ignition is designed to do!
Last edited by JTK44; Jan 19, 2020 at 11:23 PM.
I always fuel locally at Costco. Regular fuel is currently $2.029, while 93 octane (the E requires 91 octane) is $2.379. My 4 year lease is for 7500 miles per year. If I travel that maximum distance during the 4 years, 30,000 miles, at say 23 MPG, buying Premium over Regular will cost me $457 more. I paid $5,000 more for the V6 over the I4 (admittedly, I didn't have a choice with the wagon, but that's the difference with the Sedan). So, for less than 10% added cost to the V6 engine, I get to use it, without concern, instead of getting only about 200 HP. To me, that's money well spent, and a drop in the huge E-Class budget over 4 years.




At 70 MPH you use less than 17% of available Hp and 95% of that HP is used to overcome air resistance.
Everyone can spend their money as they choose. You do not have to justify using premium. As I said using premium is like changing your oil every 5,000. No harm will be done except to your pocketbook!




I am horrified about the cost of maintenance of German cars including Porsche, Audi, BMW and Mercedes (I have owned many versions of each) beyond their warranty period. I own a Porsche Boxster and routine maintenance is horrific: $425 for an oil change and automatic transmission linkage plus bearing that broke at 9,800 miles, the car is 10 years old but less than 10,000 miles, cost $3,200. Can you imagine an automatic transmission linkage breaking on an American or Japanese car in under 10,000 miles? I never heard of it, but it happened to me on my Boxster.
As I said I just do not want the expense of ownership beyond the warranty.
But you're right, we all spend money in different ways. I just happen to think it's worth paying 0.55% of the MSRP extra for gas over 4 years to know I've given my car the best chance for survival and gotten maximum performance and longevity. And that "The Note" will never be a problem with my dealer or my warranty.




None of what you post applies to you and "best chance for survival and gotten maximum performance (which you admit you will never use) and longevity" - even if you keep you car after lease for 10 years that is less than 75,000 miles.
Again using premium is like changing your oil every 5,000 miles or taking flight insurance!




Funny, people spend thousands of dollars wrapping their cars and such, but don't want to spend a few dollars on keeping the engine in the best shape. They say to never buy new, always buy a couple years old or so, but then to never buy without the automation packages that are only available on ordered new cars. But as we've discussed, we all spend differently.
Ignore that big warning NOTE if you like; I'm not going to.
Let's go our own separate ways on this, okay?
I love our 2020 E450 Wagon in Iridium Silver, Sport Styling, AMG Line Exterior, Night Package, ... looks awesome and drives great. Switch to Sport+ and even the exhaust sound gets exciting.




I am horrified about the cost of maintenance of German cars including Porsche, Audi, BMW and Mercedes (I have owned many versions of each) beyond their warranty period. I own a Porsche Boxster and routine maintenance is horrific: $425 for an oil change and automatic transmission linkage plus bearing that broke at 9,800 miles, the car is 10 years old but less than 10,000 miles, cost $3,200. Can you imagine an automatic transmission linkage breaking on an American or Japanese car in under 10,000 miles? I never heard of it, but it happened to me on my Boxster.
As I said I just do not want the expense of ownership beyond the warranty.



