I think you had better measure again unless you were doing 32 miles per hour.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

agreed, whats more likely? you get 20mpg better fuel economy on the highway than every other 240 owner? or the math is off.

Even at 32 miles an hour, you would not get 52mpg. Maybe if you towed the car idling.

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This post brought to you by Carl's Jr.

I agree. 22 is about what I would expect. I measured every tank in my 300SD and the range was 19-27 ish. Similar weight but more aerodynamic than a 123 wagon.

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1979 240D, 4spd manual, Power Sunroof, manual windows, 147k miles, Pastel gray/Black MB Tex.
1991 300D 2.5 - Smokes like it's on Crack!

Yeah, earlier this summer I moved half a small apartment in my car -- a 6 hour drive from Oklahoma City to Austin. I had a bike, a large dresser, that ladder, plus some other stuff strapped to the roof rack, plus the car was packed floor to ceiling; I mean totally packed without a spare inch to spare. Everything was maxed out. I went about 70 mph the whole way, and....

yep, I got the same 22mpg on that trip too... lol.

That is hard to believe.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

A one or two tank sample has a good amount of wiggle.

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1986 300 SDL - rolling parts car and test bed.
1987 300 SDL - semi daily driver.
1977 U1000 Unimog
2007 Ram 2500 6.7l

Lol I wish I could have seen this

A bit off topic rant: I notice that a lot of folks on here obsess about mileage. While its good to be frugal, I'd bet that the initial investment (or lack thereof) will pay for any gas difference for a newer/more efficient car. I wanted a Golf TDI ever since my mother bought a diesel Jetta in 2000. I consistently get 50-55 mpg (admittedly mostly highway) in her Jetta. Considering a used TDI golf on average is about $6000 at the cheapest these days, and a price of $1000 for an old diesel MB, how long will it take to recoup that $5000 difference? Not to mention the increased maintenance cost of a VW. It doesn't even have to be that drastic--a $1500 econobox that will only get 5mpg average better will take years to pay off the difference, depending on fuel prices and how many miles you travel. IMO the only thing obsessively tracking mileage is useful for in these old MBs is diagnosing fuel problems. I wish that in all of the craigslist ads, people were more honest about their mpgs...the first 300SD I got, the PO swore up and down it got 35mpg. I have gotten about 32mpg tops, which is really pretty good.

Edit: I'm sorry for the long rant, I don't mean it at the OP, more of a general expulsion of my time and energy this afternoon. Its been a long day at work today and I needed to get my mind off it

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth

The type of folks generally interested in diesel cars and trucks are the type who routinely will record miles and fuel usage every tankful just so they know what it is doing.

Me included.

When I hear someone who says they get the same mileage with their pickup towing a trailer or empty I always say to myself..."They obviously don't know how to calculate fuel mileage".

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Yeah I never drive my Cummins pickup out of town unless I am towing something, otherwise I would take the car. So I don't have an unloaded freeway versus city comp but loaded freeway is very close to unloaded city.

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1986 300 SDL - rolling parts car and test bed.
1987 300 SDL - semi daily driver.
1977 U1000 Unimog
2007 Ram 2500 6.7l

To the OP who also mentioned that sometimes the engine seems fuel starved for a few seconds, then is OK:

This happened to me early this year. I changed my filters and it didn't help etc. Finally I discovered it was the rubber connector that's mounted on a ball/socket style bracket to the front of the firewall ahead of the driver - this contraption has a rod going down to the accelerator pedal linkage, and changes the vertical accelerator linkage movement to a lateral one, going over to the top of the engine and moving the throttle linkage lever. Sorry if the description is lame, but go open your hood and you'll see it.

Anyway - this ball/socket/rubber link thing was falling apart, and the accelerator linkage was slipping every so often, effectively cutting the throttle back for a few seconds. I replaced the part - easy job - and the problem went away.

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Charlie

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'66 VW 1300 96K miles
'97 E300D 239K miles
'85 300D 203K miles (sold Sep 2012)

24 City
27 Highway 60-70MPH

Consistently all summer. It went from 26 to 27 on the highway after a valve adjust and air filter replacement.

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1981 300TD "The Green Lantern"
1980 300TD
1983 300D Euro "China Cat"

That ladder must have an incredible amount of drag. Just think of the wind whistling through all those steps. You've got to get a reading without anything on top to see what your car is actually capable of.

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The 240D I got recently and flew out to MS to drive back to FL and got about 32 with crappy filters and WVO partially in tank. PO had bought to run on WVO for a year before selling, I got it because it was manual everything and I wanted an economical commuter after selling the '06 Jetta TDI. After new filters, new tires in stock size and some basic maintenance I managed the 34MPG. Hoping to get better after rebuilding the injectors with new nozzles, the ones in there now look like crap and spray about the same. I'm not lead-footing nor am I babying it, the only plus I could possibly have is Florida's flat sea-level roads.

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Joe Black
Get yellow fever at ACME!

Just the MB's: '82 300DT (stick), '81 240D, '80 300SD, '80 300D, '81 240D Manual

On a 240, 34mpg makes sense, but originally you said you got 34mpg in an 81 300D turbo, which is pretty amazing for the 5cyl in the 123 chassis. Did you get that fuel economy in both?

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This post brought to you by Carl's Jr.

Yeah, my 300D turbo gets regularly 32MPG and sometimes when it's cool and the planets align 34MPG which is why I was very disappointed with that same economy out of the 240D. I now have a regular 140 miles commute while back in school getting re-edumacated so figured the 240D should be doing around 40MPG give or take. Coulda sworn I'd seen many claim the same for the manual cars.

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Joe Black
Get yellow fever at ACME!

Just the MB's: '82 300DT (stick), '81 240D, '80 300SD, '80 300D, '81 240D Manual