I drive 81 miles a day in my SD with the cruise set to around 70 in the morning, and around 73 in the evening on my way home. It runs smooth and happy at those speeds. I have the 3.07 diff. I've been averaging about 26-28mpg. Due to where I live and where my workplace is, I only have to drive on about 2 miles of city roads a day, the other 77.5 miles is 55-70mph freeway. The one place the diesels really win out is efficiency in a head wind. Even when its real windy I still get about 23-24mpg.....but our 300E will drop from 24 to 17mpg if you do a long drive into a strong head wind.

As far as max efficiency, my SD maxes out around 30.5mpg or so if you go 50mph and drive like a granny. The 300E has managed 27mpg before after a long 55mph drive.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

All this discussion has started me thinking( we know how dangerous that can be.)

Is there a place where all the available ratios and their vehicles are listed? If I decide to make a change, I need a shopping list for the junkyard.
Are all the diffs interchangeable?

I have an '82 300SD, that maybe could use some taller gearing.(lower numerical)

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1982 300SD " Wotan" ..On the road as of Jan 8, 2007 with Historic Tags

We installed a 2.47 from a euro 500SEL into my dad's '83 300SD last May.....It is still decently quick, and feels totally different while driving. (very quiet and refined) Though the diff is quite loud.....as it had fairly high miles. Looked perfect inside though. A lot better than the 3.07 it replaced! It had metal shavings coming out with the gear oil and the gears were physically worn/damaged + it had a lot of play in it.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

after 55 mph the air traveling over the car increases roughly 40 percent for every 5 miles per hour gained.

what models carry that gear?the 2.47 rear from what would fit a w123?

reread post #55. It would be the first generation that would fit the 123.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

There was a recent thread (past 5 months???) that had some of that information in it.

I should chime in here that I have TWO early w126 gassers --- the rearends are still intact. One is spoken for.....the other is avaiable. If you do a search on "2 gassers" in the Parts Forum, you will find the thread.

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daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

You have two options:

A 2.88 from a 1985 300D or 1985 300SD.

A 2.47 from any of the V8 gassers from 1981-1985.

My '79 300SD autobahns happily at 90mph ... well-tuned and always biodiesel fueled