I would question that the wagon is more aerodynamic than the sedan. It has a taller roof line and a luggage rack, and a good deal more weight. the weight only matters around town on mileage.

What were they rated for mileage when new?

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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.

I've been averaging 23.8 mpg highway driving between NJ and WV. Running down I81 at an avg speed of 75 mph. Like everyone has said many things can affect your mileage, including driving habbits. I have a 190E and when I drive the car I get about 24mpg,, and when my friend drives it. .he can barely get 19mpg!!! Of course I am not as heavy footed.

Oh.. my wagon has 245K on the engine and almost 400K on the trans and body.

Like everyone has said here.. filters, valve adjustment and IP timing can all effect your mpg. One last thing I would check, is the banjo bolt on the rear of the intake manifold. this is a prime area for the boost line to clog. Clogged boost line causes lack of power or boost when you step on it, and maybe causing you to push it harder, dump more fuel and drop your mileage.

I drive my wagon in the City and get around 21 mpg. Whenever on the freeway, if it's not a slow commute, I'm doing 65-75 mph.

On a recent 5.5 hour roadtrip to Fresno (don't ask), the wagon got 22 mpg on the way and 25 mpg on the way home. I attribute the better fuel economy on the return trip to lack of A/C use. We carried an extra few hundred pounds with us on the way home too, which didn't seem to bother the vehicle one bit.

My average speed was in excess of 70 mph on the freeway and at times the speedo was pegged. You might do better at 55 mph...but what's the point.

I've never gotten better than 25 mpg and the wagon is up to date on filters, valve adj, etc.

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1982 240 D, 308,000 - 321,127 miles (sold)
1982 300 TD,166,500 - 226,000 miles
1998 E 320, 120,000 - 144,000 miles
2005 C 230 K, 26,000 - 77,000 miles (sold)

taller roofline? Never noticed; I do know that it's as low or lower than a lot of modern cars I see on the road.

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1982 240 D, 308,000 - 321,127 miles (sold)
1982 300 TD,166,500 - 226,000 miles
1998 E 320, 120,000 - 144,000 miles
2005 C 230 K, 26,000 - 77,000 miles (sold)

I could be wrong about that. Old Volvo wagons do but I am not sure about the benzes.

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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.

There is no doubt that the wagons are better on the test track. MB testing engineers used wagons instead of coupes or sedans. They have a lower drag co-efficient. FI's got it right there- lower drag but heavier so it's a wash.

Just checked my mileage from comming back from another WV trip. Got 26.2 mpg on the highway keeping an avg speed of 65 mph. ANY way I try to come back to north Jersey involves hilly country winding roads with speed limits of 40 mph or so.

1982 300TD

For a 1980 the 300dt is rated the same as 300td epa, according to my old chilton's diesel book.

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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.

I drive all in town. A/C occasionally. Spirited driving, i.e. NOT trying to
maximize mileage, just to have fun. That returns 20-21mpg consistently.
Took one full tank trip at 80mph no A/C useage, 25mpg, not trying to
produce good mileage at all. That's just fine with me. Sunday car gets
9mpg in town, 15mpg on the highway, driven in the same manner.

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85 300TD FED-Daily
84 300SD-Wife's
86 XJS-Sunday
66 GMC-Work- Given to my stepson
83 BMW Airhead- Given to my stepson

Over several thousand miles, I get just short of 23, avg. as low as 17, towing, and as high as 28.

I do not drive to conserve fuel, I usually am at the speed limit or then some. city-highway does not seem to affect it much.

I did remove the thule bars once and gained 2 mpg on that road trip- but ity could have been other factors, too. I know if I haul something on the roof, it really kills the mileage.

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.

I mounted 15" steel rims with 205/75 tites. The RPM dropped by 10% so I hope I get some better than 20MPG. The ride is super nice on the highway and the tires are stiff enough for stability.

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Good Patina Comes With Good Miles Driven.
Drive more polish less

220SEB 1963 (excellent driver with no rust but far from pretty)
300 TD Wagon 1981 (Daily Commuter Tractor)
911 MFI 1973

www.vintagemotion.com

Mine averages around 25 mpg consistantly.

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Brad
1981 300TD - daily driver
1963 Chevy II
2001 F-250 7.3 Power Stroke

depending on driving style--fast acceleration and town driving influence mileage considerably. On the highway they do benefit from the better rear end aerodynamics--the extra weight doesn't really matter with relatively constant speed. The difference in mpg between 55mph and 65mph is considerable. I consider the stock gear ratio ridiculously low for highway driving.

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1999 E320 4matic really nice Wagon 135k
1981 300TD loud, rattling family car 180k (TGI sold!)
1985 500SEL gas guzzler 220k (sold)
1978 300D my first Turtlediesel (sold)437k