On this tank of gas, I have gone 376 miles soo far, and the low fuel light hasn't come on yet (it's about to).

Most I have ever gotten on one tank. Word.

 

must be driving downhill all the time

 

My C280 gets around 19 mpg on the highway and once in a while I might get 20mpg. But I have a heavy foot. I didn switch to 91 octance instead of 93 octane and now 19mpg and more often 20mpg seems to be the standard. Around the city 16 mpg to 17mpg. At $229.00 a gallon I never got below 1/2 tank.

 

I once got 549! I don't know how I got it, but I made it from New Mexico to Phoenix. Part of Arizona was down a mountain. Normally I get about 290 per tank. What does everyone else get?

Can you explain this? Is it better to fill up before 1/2 tank?

Nick

 

I'm at 387 miles now. Wow. REally need to fill up asap...

 

It might be a problem, I do it due to the high cost of gas, I know you could agrue, what is the diiference eventually it all works out to the same amount of money. But I feel better spending $20 more or less then $35 plus to fill up the tank. I was at a station today and some person with a Tahoe put $65 dollars of gas in that thing, I would drive a old beetle before I had to spend that kind of money on a tank of gas. A co worker of my wife, husband has a Hummer, which is now 3 or 4 months old. He didn't "realize how much gas it burnt and how much it cost to fill up." My comment to my wife, was serves the idiot for not thinking about what he was buying. God Bless him if he sells it around here. How he could afford it is beyond me, he is a factory worker and isn't rich, or perhaps he is, whom am I to judge anyone.

One thing I know it's not good is to let your tank run down to the bottom, seems stuff collect down there and could mess up the fuel system, but this was told to me years and years ago, perhaps with modern cars it doesn't, apply. One last point I try and keep the tank as full as possible in the winter so condensation doesn't build up in the tank.

 

Wizard,

You must have a real heavy foot. In mixed driving I'm getting 26 mpg. I've had my '99 C280 for 2 days now and done two different mpg tests.

In the tests I'm leaving it in overdrive. I accelerate at a modest rate around town, use cc frequently, and cruise at 65mph on the highway.

Test#1. 85miles-3.2gal. Test#2 80mi-3gals.

BTW, This is not my typical driveing style, however, it is nice to know I can get these results.

BTW2 Adding a K&N high-flow air filter or even a cool-air intake, one should get even better mpg results. ( of course what usually happens when you add a cool-air intake is you improve throttle response and end up getting worse gas miliage because we like the extra 'umph" at take off.)

 

Yes, I admit I have a heavy foot, but not that heavy, Also, I don't drive much do to a bad back. In a recent artilce I read in a UK publication, The article postulated that the less you use these cars, Mercedes Benz's in general the more things go wrong or fail, one thing mentioned was gas mileage. Actually the ram air intake is off the car. As I decided after I took the bottom of the air box out, I had the intake's stainless steel tube cut to short to attached and have it rigid, especially the lateral motion. I have another piece of tubing which is not stainless but aluminum, a bit lager diameter about 3 1/2 inches and I'll have it mandrel bent and sized, and look for brackets that are "stronger and attached it closer to the air hour. Your correct the gas mileage seemed at first to be better, but, as you side the tendency with these intake is to hear the intake hose and you have to almost full throttle the car to hear that. Thanks for the advice. I haven't taken any trips since my son replaced the ram air with the stock air box, but what driving I have done, seems almost lazy, even driving it the way I did the ram air intake equipped automobile. I am getting close to the 50K miles on the odo, and I really wonder if the car needs a set of plugs, but my finances are low at the present and I don't have the confidence to replace the 12 plugs myself, as my confidence in removing the coil packs is not high. After reading a couple post on other boards writtten about how easily these packs can break. Also, I don't have the correct wrence for the coil. I am supposed to as you, have 100K plugs, but as I wrote I only clocked 28K plus miles on the car in almost 3 years of ownership and if plugs are still plugs, lack of mileage will build up carbon deposit and lower gas mileage quite a bit. What my car needs is a good run down the eastcoast to Florida and back. Thanks for the info.