On Monday, I drove 478 miles from Ohio to New Jersey mostly on the PA Turnpike. I used the cruise control as much as possible and averaged 71 miles per hour for the whole trip.

After I got home I filled up the tank and took out my calculator and I averaged an astonding 29.3 miles per gallon for the entire trip on 89 octang.

Is this un-common, was it becasue of the cruise control, or are you all seeing the same thing?

 

on the wrong fuel
you are only supposed to use 91 high test.you could have gotten better mpg had you spent the extra dime a gallon
I average hway at steady 80 about 27.5 in the 99 E320 wagon.Without
hypermiling better than that if I do.
ohlord

 

99' 4matic wagon from newport beach to cambria/hurst castle 55mph hwy-80mph freeway{even over the grapevine} with wife kids and gear. average round trip 28 mpg!!! love my wagon!!!

 

I average 20 in the City and 25 on the Highway....... As long as I keep it at the posted speed limit. I just made a trip from Phoenix to LA on the way out I averaged around 83 MPH and got 25MPG on the way back I averaged 95 and got 22.5MPG. The trip out took about 6 hours and the one back was less than 5. Man I love my E55!!

 

I get close to 30 on the highway at 65-70mph. Average mixed driving I get around 21. These cars do great on gas for their size.

 

I think I get slightly less good mileage with 91 octang than with 89. I tend to mix the two...depending on the price.

 

I just drove from Florida to Virginia over 850 miles. My best mileage according to the computer was 25. This if I drove not more than 70MPH..
Not bad at all for a 4.3 litter 4matic.
( I always use 91 octane)

 

Got 25 mpg from Tucson to San Diego in my 97 E420 at 70 - 80 mph with 4 people and crammed trunk. When I got to SD I found my pressure was low, so might have been a bit more. Don't know what I get around town, haven't had the car long enough to refill yet.

todd
97 E420

 

I average 24.6 from ATL to PA (750 miles +-)

Speeds between 55-80.

 

my e320 gets better mileage than my ford focus

focus...17-18 mpg city and 25 mpg highway
my e320 18-19 city and a whopping 30 mpg highway

the economy from my benz is amazing

 

but just to see if my theory worked or not, I was traveling on the highway as well as the street and for both places I turned off my DSC. My MPG calculator on the dashboard started to go up. Was it due to me turning it off or just a good day?

My theory being that DSC is constantly working and checking to see if my tires are not slipping/straight, turning it off would make my car travel a bit "less bothered" and thus create better MPG.....

Am I crazy or what?

 

This is likely calculation error as this is impossible.

 

bump

 

Made 1380 mile round trip from Connecticut to Ohio (Columbus) in a 97 E420, got right at 25 MPG cruising at 65-75.

 

Did a club ride this past weekend from Pittsburgh to Lake Erie. Averaged 30.4mpg round trip at 63mph set on cruise S210 03' wagon with 3.8L motor. 250 miles all totaled. Wife's 97 Accord still beats me at 36mpg at same speed with 228k miles racked up. She came up late and followed me home. Great mileage in these 210 cars for the weight and amenities they offer.
BYW how many of you use Mobil One full synthetic oil? It is all I have ever used in any car.

 

Since I got a hold of the car, that is the only oil going in and out of my car.

 

That can't be correct.

I have thought of doing that here, but our Plus is 89 and Supreme 93. If I could get it precise I could save 10 cents a gallon when I use the lower grade and run on 91. I have not tried that yet, because it's not worth the effort.

 

How's this? Drove my beautiful E320 from Columbus to near Cinn. A/C on the whole way. Over 30 MPG!!!!! To top it off, when I left the outlet mall a couple parked near me....way out in the lot.....said," nice car, is it new?"

 

I'll vouch for that. I've gotten over 30mpg on the highway and when I detail it (almost every weekend) I get comments all the time. Does better then a 4 cyl Camry or Altima and that's with the original spark plugs. We keep the Suburban parked and use the E320 all the time to save gas.

Bought new plugs, air filter and serpentine belt. Just waiting for a few free hours on a "not so nice" weekend to spend doing tune up although the motor still runs like new with 93k miles. I did the transmission fluid, filter, and electrical connector change (slight o-ring fluid leak, very common) a few months ago. Love this car.

 

I just came back from NJ and PA today. Here is my new MPG reading! I went up to 70-75MPH from time to time. I thought it would be impossible to get over 27MPG from V8 E430 4matic.
Here is the result;

 

I've noticed more than half the time the mpg on trip computer is about 1mpg higher than I calculate manually everytime I fill up. i.e. the computer says 22, but I caclulate 21.

I'll have to reset the computer and let it run for 1000 miles and compare that to actual gallons purchased one of these days to compensate for the different pumps I frequent.

 

From what I've gathered on here, Robert is correct. The car's trip computer is not accurate. The best way to measure MPG is to reset your trip odometer to 0 when you fill up. Then when you fill up the next time, divide the miles driven by the gallons you add.

 

What is your reference point to refill the tank? Is it when the empty tank light turns on? Or taking any measurement point on the gauge as a reference?

I would wait until the light turns on. Then I would fill 10 Gallons and set the trip. Drive until the light turns on again and check the trip reading.
Then I would compare this with the computer result.

 

It does not matter. Just as long as you know how many gallons you add during the re-fill, and how many miles you drove until the next one. I don't think we can completely trust when the add fuel light comes on. You have probably noticed that it will flicker on and off during right and left turns when the fuel level gets that low.

 

I always fill up until the pump clicks off, then gently squeeze it one more time until it clicks off again. Depending on how sensitive the pump is, it may shut off sooner or later than another pump.

I don't like to wait until the light turns on, I just can't handle the pressure. Seriously, I'll start sweating until I find a gas station.

Otherwise, assuming I can get to a gas station immediately after the light comes on, your method seems sound.

Either way, I think resetting the trip computer then letting it run for 1000 miles should average out the differnences in pump clicking or light chasing.