Crunching the Numbers

So which figure is not correct: the mileage rate, the fuel tank volume, or the odometer? Because 706 miles at 34.6 mpg converts to 20.4 gallons. The article states 21+ gallons available. Was 34.6 mpg the overall fuel economy or a rolling average economy?

Arthur Desrosiers, Richland, WA

FCR: Despite the fact that they control nearly every aspect of the modern automobile, and are probably capable of landing a man on Mars, on-board computers still aren’t perfect at calculating fuel mileage, and neither are we.

Fact: the E320 covered 706 miles.

Fact: the E320 has a 21.1 gallon tank. (The M-B specifications sheet lists a 2.4 gallon reserve, which we later found out is inclusive of the 21.1 gallons, so forget the 23 gallon figure mentioned in the video.)

Using those numbers, the lowest possible fuel economy achieved by our E320 is 33.5 mpg, though it’s quite possible that the full 21.1 gallons didn’t make their way into the engine. Unfortunately, since roadside assistance brought an unknown quantity of fuel, there’s no way of knowing exactly how much was consumed on the trip. Even if only .5 gallons were left in the tank, the figure would be greater than 34 mpg.

Diesel Cars Rock!

I think diesel cars are the wave of the future. Fuel economy with modern diesel engines is better than gasoline. I drive a VW Jetta Diesel using commercial Biodiesel fuel whenever I can. My wife drives a Dodge Ram diesel pickup truck, again using commercial Biodiesel fuel whenever possible.

Chad Pence

Double Down

I drive 120 miles round trip to work everyday 6 days a week.

I’m in love with just the thought of getting 700 miles on a tank of gas.

That’s more than twice what my Blazer is getting now (325 to a tank).

James Gore, Clarkton, NC

Sailing Down the Highway

I own [an M-B E320] and have gotten 39 mpg on the highway with a good wind behind me. They are wonderful cars and what economy.

Darrell Ward

FCR: We wish you could’ve passed that wind on to us.

Long-Lasting Gas

I enjoyed reading your article on this car. We bought an E-350 [gasoline-powered] last year and it gets an honest 29.1 mpg on the highway at 70+ MPH, at least according to the computer display inside the speedometer. We're real happy with the car, and they sure are beautiful cars.

If the diesel only gets 32 mpg then that's barely 3 more...not sure you would make up the difference on the higher purchase price and significantly higher price for diesel — about $0.50 more here in the Atlanta area, or about 14 percent more than premium unleaded, yet that car only gets about 10 percent better mpg than our E-350. I thought about going for the diesel last year, but am now glad we just got the gas model.

Jeff Marken

FCR: Marken makes an impressive claim that would represent a 25 percent increase over the estimated fuel economy for the E350. While we can’t verify it, if true, it shows how much you can affect fuel economy by merely adjusting your driving technique. In any case, any fuel saved is fuel saved, and the popularity of hybrids indicates that many buyers are willing to pay a premium to lower the environmental impact of their driving.

Always With the Prius

Just another expensive automobile that may get a little better gas milage than another expensive or less expensive one. I'll keep my 2001 Prius with 138,000 miles that carries 5 people. Sufficient luggage capacity, and gets 48.0 mpg with good performance and driving qualities. Oh, I must not forget that the brake pads and shoes are still original and I calculate them to last till 200,000 miles. Oops!! I did replace the main battery at 137,700 miles at a cost of $3,800, parts and labor, but I'm still ahead for what I had saved on gas, and still am.

Robert Bosak

Hitch a Ride

If you take a truck driver with 20 years under his belt, or a race car driver, they can show you how to increase the mileage you got by 10 percent.

Eddy Lucast

FCR: If you know someone who’d actually be willing to spend 12 hours in a car with our reporter, we’re not sure we’d want to meet them.

Because the Car Was Lighter Without It

Why didn't you keep a container of gas in the [trunk] in case you ran out?

Charles Carbone

FCR: You must be a lot of fun at parties, but we’ll never know, because you’re not invited.

Difference of Opinion

My god man, who taught this person how to write?

Rex Cauldwell

FCR: The question was, “what do you think about the E320?”

I know nothing about cars, wouldn't be considered a 'car' person and all the female stereotypes as they pertain to women and cars probably do apply to me. That being said, this was a great article. I actually read it all, which is unusual I am more of a 'keyword' person. Anyway, this article was very well written and informative. Thank you, I learned something new today and it involved a car — go figure!

Michelle McCoy, Hermitage, TN

FCR: Lady, you can answer any question that you want to.

Diesel Dreaming

As an owner of an E320 4-matic [gasoline-powered] I get 27-28 miles a gallon (Not bad for such a large car). I drive this car every weekend to my house in Fincastle, VA, from the Pentagon and I will attest to this car’s comfort and performance … I really miss driving my Benz while I'm here in Iraq and I would love to own one of the diesel ones since the distance from the Pentagon to my house is 225 miles one way. Great car. Great article.

Dale D. Fair, LTC, ENMulti-National Security Transition Command-Iraq

FCR: We hope to see you back behind the wheel too. Stay safe.