Fifth Ring

I decided to try for maximum gas mileage on my current tank of gas. I'm currently more than 1/2 way through it and the computer readout shows 19.8MPG. Average speed is 29MPH which is actually high given my typical driving day (mix of hwy and local).

That's pretty painful. Sure, it's a powerful fast car, but I'm driving it like an old lady!

bmjdevelopment

I just did the same. I averaged 22.4 mpg on the last tank. This one I have opened it back up and I am at 18.6 mpg. This is on 2005 C55.

TopGun32

I'm hitting 20mpg around town and 25 fwy.

bad i have to drive under 70.

loungn14

Darn...you guys are too much...

Im lucky to get 18...but then again...its just too hard to drive nice...

Tump43

I managed once to get 21.8 mpg in mixed town & highway traffic by driving as if the car could not accelerate. It was too painful. I too am back at 17.1 to 18 mpg on my C55.

Kablouie

I believe that my right foot is heavier than the left - I can't seem to break 17!

ScottW911

Ha! I guess I might be the winner (or whiner, as the case may be). I struggling to get 14 mpg.

c32AMG-DTM

Yikes, that's horrid.

I routinely get high-teens, low-20's, depending on the highway/local mix. Might drop off once I have some mods installed... we'll see

moosejaw

lay off the supercharger
try to avoid going past 2300Rpms

TemjinX2

i usually get around 20-22mpg average hwy and city. But i'm on stock wheels and stock tire size.

Key is try to keep the same throttle position from a stop to 40mph in city. The car has enough torque to get you going at a decent speed. Keeping the car at a constant light throttle position keeps the mpg up, hence why you usually get more mpg when you use the cruise control.

Also check tire pressure, this can save you 1-2mpg straight off the bat.

Keep the climate control off and windows up on the highways. Maybe dumping the spare if your in a city area with roadside assistence or AAA card.

MRAMG1

Hate to be the bearer of bad news, but consumer reports and several other groups on AOL/Motortrend, etc, have all proven that tire inflation, +/- 10 PSI does NOTHING for gas milage. Sorry guys, but it is a myth. Maybe we need Myth busters to debunk this one

See yeah

PS: my best, 660 miles from St Loius was 24.6 averaging about 80. But I had a Bad I/C pump.

Usually I get around 18, and at the track, 7.2

loungn14

ya...mythbusters..gotta love it.

but..7.2 at the track! Yikes!

loudandheard

I was having trouble reducing my gas mileage, but I noticed that I was driving a little too fast, but if I mix in a bit of spirited driving and stay at a consistent speed, I'll average a minimum of 20mpg.

Al Bundy

I can beat you all!

I live downtown Chicago and usually get between 8.9 and 10.1 MPG on my daily commute across the Loop. On the second screen that doesn't reset, I'm averaging 12.1 over the last 1,000 miles.

Good thing I only drive about 5 miles a day or this would be quite expensive.

c32used

I usually get high teens in local roads and like 21-23 on highways...

ohlord

crap coming out of AOL
A 2-4 psi increase front and rear will increase mpg.And being 10psi
under inflated
will overheat a tire to the failure point.No need for myth busters the cranks you noted haven't a clue.
don't know where you got your info
but here's the CR report
http://blogs.consumerreports.org/car...tire_pres.html

and from Luke at tirerack
http://www.tirerack.com/tires/tirete...e.jsp?techid=1
Go get a good digital gauge and use it,you will be surprised at the mpg you gain by having them inflated to spec or a few psi over.

e1000

https://mbworld.org/forums/c32-amg-c55-amg-w203/241527-c32-versus-c350.html

MRAMG1

Well Hi there:

Okay try this one

http://www.edmunds.com/advice/fuelec...2/article.html

In their words "No measurable effect on the vehicles we tested"

You, okay tirerack, are correct about temperatures, but I can personaly tell you that I have raced, at 145 mph on tires only inflated to 20psi and lived to tell the tale. Try changing your tire pressure to say 38psi, I wouldn't want you to get hurt on low pressure, and I'll take the bet you WON'T notice ANY change in your milage. Providing that you drive the same my friend. Don't want an argument here, but the fact is the change in air pressure/ rolling resistance is SO SMALL, it just doesn't matter.

See yeah

Fifth Ring

Experiment is over. I got 20.1 MPG. I filled 'er up last night and I think I'm going to enjoy the HP rather than the extra 2 MPG.

///AMG4EVER

So I was thinking about MPGs this morning and decided to give it my best try. In all fairness, conditions were perfect.

My commute is 20 miles. Weather in the low 70s. 6:45 AM to beat traffic. Mostly flat roads. 90% hwy / 10% city. Reserve tank light on. AC on (2 bars). No passengers. Drive was under 2,400 rpm.

I manage to squeeze 28.0 mpg, 50 mph average, 23 minutes.

The best I saw was 29.1 mph on the highway with cruise control on at 65 mph.

The car has 110K miles with the following services done recently: engine oil & filter, clean current K&N air filters, trans fluid & filter, fuel filter, new spark plugs and ECU reset. All in less than 2K miles ago.

On another note, I went directly to the gas station and for the first time I filled it up with $60.00 (15.15 gallons at $3.96). I'm not sure about the tank capacity but I think is 15.3 gallons.

I'm with you Fifth. It's nice to see these figures but it was painful to drive and absolutely boring.

ohlord

When you read and quote an article it helps to read and quote the article
where did you arrive at "no measurable" from

" But is it important? The answer is yes, for a number of reasons. Properly inflated tires are less likely to fail at high speeds. They wear more evenly and, yes, they deliver better gas mileage. How much? In this test we saw a modest difference in two of the cars. It might have been more dramatic with different tires on different cars."

To which they add

"Eventually, we concluded that each set of tires is different and every vehicle is different. We recommend that you do your own tests to see what inflation setting gives you the best fuel economy."

So A. read the article B.properly quote it. C. In 40 years of racing cars I have been past 145mph many many times and if the tire was below 20psi it was a slick on a 1957 chevy.If it was over 145 in one of my sports cars the tires were properly inflated
What tire were you running intensionally under inflated at 20psi at 145mph and on what car?And why if you did it on purpose were you doing something so stupid?

by the way a MODEST increase of 2mpg on an average 15,000 mile per year car is 69 gallons of high test,don't know what you are paying for premium
in the land of misquoteem but if you can save 69 times what ever you pay per gallon,and choose not too then We have the answer as to why you would drive on purpose with under inflated tires.at over 145mph
See Ya
ohlord

MRAMG1

All I can say is WOW

The quote is, as I stated

Test #5 Check Your Tire Pressure

Result: Important for safety and to reduce tire wear

Cold Hard Facts: No measurable effect on the vehicles we tested
Recommendation: Check your tire pressure often but don't expect a big savings.
WOW, thats somes it up my friend

See yeah

PS: Crew cheif advise as to tire pressure due to understerring, so we dropped the rears, that is IF you can understand it my friend

ohlord

the article.Like I said if you choose to **** away 69 gallons of fuel,we know where you are coming from.
If you were running race tires at 38psi and you had a problem with understeer,a drop of 2-4psi would be sufficient to correct the problem,a drop in your case of nearly 40% should have been cause to drop the crew chief.That sums that up
ohlord
while you are at it read the other article they link to when you take the time to read the entire test
http://www.edmunds.com/advice/fuelec...8/article.html

Al Bundy

Keep in mind that most of my commute consists of a dead stop where I get 0.0 MPG...

loudandheard

Would we get better gas mileage if our supercharger did not engage? If that's the case, what if there was a way of turning off the supercharger so that we could improve gas mileage.

I don't know if I could drive the car with out a supercharger, it would feel dead to me.