For almost 25,000 miles, carefully recorded fuel input shows 25.5 mpg in an 82 300d. SLightly higher in summer, lower in summer, and of course higher on a given time when mostly highway miles.

I will echo the observation about summer/winter. Seasonal temperature seems to be the most important variable in my overall milage. Closer to 25 in summer, closer to 22 in winter.

another factor in winter mileage is winterized diesel fuel. Winterized diesel is #2 cut with kerosene which has a lower heat content (btu/gal) than straight #2, meaning you have to burn more of it to go the same distance or achieve the same HP.

'85 300D, 25 mpg city 32 mpg highway with a/c on. Delvac 1 oil, all repairs and maintance done myself. Usually I run Amoco 47 cetane.

I get around 30mpg with my TD (with 4-speed manual), mixed driving and not going over 70miles/hour.

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1974 240D, 125K mi, B100 now, SOLD
1980 300TD, 115K mi, 4-speed stick, roll-up windows, greasecar with two tank conversion (daily driver)
1985 300D, 220K miles, greasecar with two tank conversion, SOLD
1993 300D 2.5turbo, 158K miles, green/tan, B20-B50

I've gotten as high as 28 mpg and as low as 19...

I attribute the 28 to the use of Powerserivce(I used it for three weeks)

and 19 because I did alot of city driving

but last week I averaged 24.5 mpg.. .and thats with a heavy foot

The only way to determine mpg is to keep a log of miles and fuel. Filling a tank can vary each time. My '83TD with 4-speed conversion will see 28-30 beating around town and 32 or better on the highway if I keep the speed under 85. I've calibratated the odometer using the mile markers over 50-100 miles and you can also get a real accurate speedo calibration at the same time.

Hello Chad,

I was typically getting 25 around town and 28 on the road cruising at 67 or so. I think you should be right around that. Also keep in mind that it will go down in cold weather.

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Doug

1987 300TD x 3
2005 E320CDI

um, post a picture of your speedometer... I bet it has a silver button on the dial. that would mean you have the speedo/odo of a 3.46 gear rear in a car with a 2.88 rear... that would just about double the distance figure...
.... wait, it would LOWER your figures... not raise them. hmmm. perhaps somebody changed out the rear end? that would do it. if they pulled the rear from a manual car or a N/A automatic it would seriously alter your calculations.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I would chalk that up to the seasonal fuel. No. 1 diesel fuel is sold in the winter where it gets cold. It has a lower BTU content than No. 2 Diesel .


Edit: Maybe this guy who got 40mpg topped of with residual fuel oil which has a BTU content of 149,000 BTU a gallon instead of No. 2 Diesel which has a BTU content of 139,000 BTU a gallon.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

How are you calculating fuel use? The only way to do it, is to fill the tank, reset the OD, drive the car. Then when its time refill the tank and note how much fuel when into the tank.

The easiest way to check that your gauge cluster is correct for the size tires and rear end is to just pace someone with a known good car and make sure you are close. A portable GPS would work too.

As stated before in this thread, you should be getting mid 20s. However, I have seen people get over 30 MPG in 240s, but they are super gentle accelerators and drive 55 on the highway.

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1977 Mercedes 300D

I had the same problem when I first got mine. I tried to reset the trip odometer on my innagural drive (500 miles) to see MPG, and it hindered and eventually stuck the main and trip odometer. I have jimmied it enough to where both odometers now operate.. I don't reset the trip odo anymore....

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85 300CD Turbo "Das Polluter" 230K sold for $3,000

98 BMW 323is