thwalkerjr

Took a long road trip yesterday and was pleasantly surprised with my MPG at 18.2 - I averaged 80MPH on a 144 mile trip.

Anyone know how to estimate what my MPG would have been if I had gone 60MPH? I'll never know 'cuz I can't drive that slow but curious indeed. Thanks

Savoy6

funny how you guys in other states think 144 miles is a long road trip. thats to the grocery store and back here in texas hehe. Back it down to about 75 and you should get almost 20.

pmknapp

I get about 22.6 to 23.1 MPG on my short road trips to work, about 75 miles one way. That is doing about 75 MPH and here I have lots of hills to drive up and down. But overall good gas mileage. But have been down to as low as 6 MPG when playing. Overall I log each fill up and log all mileage and I am doing about overall 18.9 MPG since I got the car on May 2008 and 43,000 later still going stong.
Be safe, HAVE FUN

MB_Forever

The highest mpg I noticed on a freeway trip was 23.5 mpg. However, Juicee63 has hit 24 a few times in the past in his CLS63.

ChrisD63

the best mileage ive got was 23.7

Earlyapex

I drove to the track and back with a few lapping sessions in between and averaged 6.9mpg

Sincity

On the freeway, I get about 20 and change which is similar to my RDX with half the power.

rockjock

I estimate it to be better then 18.2.

sflgator

I've also been gettibg between 19.5-20.5mpg on the hwy...fairly pleased about this.

EuroB6

i drive about 6 miles to work each way in some stop/go traffic and when I drive in C mode, I get anywhere from 15-19mpg. Believe it or not, I havent been on the highway with the car yet. I need to start driving it some more i guess

MB_Owner

Although this is merely a wag (wild-***-guess) based upon an "average vehicle" DOT study, every 5 mph increase above 60 results in a roughly 7% decrease in mileage. It's not linear but will give you some idea.

In general, smaller, lighter, more aerodynamic cars get their best mileage (the so called sweet spot) at higher speeds. And conversely, larger, heavier, less aerodynamic vehicles like SUVs get their best mileage at lower speeds.

That "sweet spot" is influenced by a multitude of things like the rolling resistance of the tires, friction in the car's components, accessories power draw, frontal area, drag coefficient (Cd) and even air density to name a few.

Reducing the Cd pays big dividends in moving that sweet spot to the right as does reducing the accessories power draw...one of the reasons M-B is implementing technologies like reducing the power steering pump pressure at higher speeds, freewheeling the alternator when the battery is fully charged, etc.

Cap_Scarlet

I did around 400 km on the autobahn yesterday with a mix of driving, going up to around 240 kmh but trying to hold 180 - 200. Lots of stop start (avoiding the dutch in the outside lane ). Averaged around 15.6 litres per 100 km which is around 18 mpg (English)

E55AMGFan

Thats amazing, 6.2L 7 speed tranny (which is doing a big help with the mpg) and a light foot of course in C mode gets the C63 mpg to comparable smaller v8s. Of course that statement is gone as quick as your gasoline if the right foot gets planted down.

propain

Almost 2K on mine now. Average 14.3. The computer has never been reset so it accounts for all the milage on the car.

thwalkerjr

That's what I normally get too. This is combination city/highway and punching it every chance I get!!

thwalkerjr

Thanks!!!! So if my math is right - using 7% as the decrease, I could have seen 24.3 MPG had I gone 60 MPH the whole way. Pretty cool.

80 18.2
75 19.6
70 21.0
65 22.6
60 24.3

MB_Owner

That's much better than the 13 mpg I had on a new C63 engine in THIS thread. Somehow I think 24 would be a dream.

EuroB6

it's funny, my previous S4s(V8 models B6 and B7) that I had, averaged about the same, if not, worse than what I am getting with my C63, so I am extremely happy about that.

NORTH 44 C63

Full day Sept 9th at Mosport International Raceway.

Averaged 43.9 Ltr/100Klm or 5.36 MPG (US) / 6.43 MPG (IMP)

The M156 engine love gas on a road course!!