Accuracy of trip computer for gas mileage




Also, the 550 probably got a green award because of the very very low emissions. It is a very clean burning engine for something of it's caliber (5.5L V8, that is a huge engine). MB engines have always impressed me.
But yes, the computer is a "little" too optimistic. I get about actually 1 mpg less than what the comp says.






Also, if say I'm at 65mph and its in 7th, and I downshift one, it goes to 6th. The way I understood it is that if you downshift, it goes to one lower than where its at, so if you downshift and it says "5" you were just in 6th (even though it says "D").

Do this .. get on the freeway, get to 75mph, turn on cruise, then go to the trip computer that is based on "start" and reset that screen only. Now watch it. You absolutely have to get over 20mpg over the next 20mins driving at 75mph with a reset "start" trip.
The Best of Mercedes & AMG
I do notice a significant decrease in MPG when I'm heavy footed or in stop and go city driving in hilly areas. In those cases, my average since start drops below 20 mpg.
I guess I'd be bitter too if I bought a E320 CDI and found out a beast like the 550 was getting "good mileage"

I do notice a significant decrease in MPG when I'm heavy footed or in stop and go city driving in hilly areas. In those cases, my average since start drops below 20 mpg.




I'm in the process of doing that now on a tank of gas to see how close it is. If you can't get past 20mpg on the highway, that does seem low to me (I don't have a 4matic).

Then go in and reset all 3 screens start trip, since reset, and the range screen. This should reset 3 different calculations.
Now at your next fill up divide your miles driven by gallons and compare to the "reset" screen.
You can play around with it and see how it goes. You'll see how easy it is to kill your mileage by driving aggressively.
Sounds like your car is working just fine. Remember, 4Matic cars get 1-2mpg lower than the regular E350's.
1) different tire pressure will yield different results
2) type of tires will yield different results
3) staggered tire setup will yield different results
4) all of the above
There is so much more that goes into this. So all these posts with different values need to find a common denominator for a good comparison.
$0.02
1) different tire pressure will yield different results
2) type of tires will yield different results
3) staggered tire setup will yield different results
4) all of the above
There is so much more that goes into this. So all these posts with different values need to find a common denominator for a good comparison.
$0.02
1. weather conditions
2. temperature and humidity
3. road surface
4. wind
5. elevation changes













