Miles Per Gallon on 1990+ Diesels

Does anyone have any experience on this for the 1990 diesels. My 1983 SD gets 30 on the interstate highways. 22 around town.

I know that if you have to ask this you can't afford one; however, I am curious.

thanks,

Tom D.

Reply to
Tom
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My '91 300D 2.5 gets 27 in a commute that involves mountain, freeway and city driving. On the one cross-country drive I've taken with the car so far, it got 33.

Geoff

Reply to
Geoff Miller

My 83 SD gets 25 around town and about 22 in the interstates, likely because I drive between 75 and 85 mph. The newer 300SD (early 90's) gets better mileage mainly due to more recent technology, 1 more gear in the transmission and the car is lighter. The newest ones (2004) have the new fuel system and get 40+ mpg on the interstate.

Reply to
dkmcp

when did the SD get a 5 speed speed auto box???

and your MPG is poor compaired to every one else i have heard from. 27 city 29 highway 75+ MPH

just a question.

the case, minus a few cans!

Reply to
pool man

I feel my diesel needs the fifth gear... I wondered if it is possible to do so and also wondered how much more fuel mileage we can wring out of our diesel...

Reply to
Tiger

i found my 5TH gear in the trunk. upon removal it got better mileage.

it weighted a ton.

the case, minus a few cans!

Reply to
pool man

I believe the 85 or 86 and up transmisions have an overdrive transmission and my 83 does not. The rear gear ratio changed sometime around then as well. I run my turbo full time (Texas Tune) and if brake-stalled will actually lay a patch of rubber and chirp into second. My mileage has been taken with the actual odometer readings, I run 215x15x65R tires and my speedometer is out a little. With the turbo running full time my mileage may be affected, but after driving this car for the last 120,000 miles my mileage is pretty accurate. There is a big difference in mpg when running at high speeds (3,500 rpm).

Reply to
dkmcp

never thought of the lock up as a gear. how dumb can i be!

don't answer that please.

as far as the rear ratio been changed that can be over done but am sure everything was thought out first.

my 82 seems like it turns more than my 84 did but the TACH needs a wire fixed so i don't know what its turning RPM wise.

the case, minus a few cans!

Reply to
pool man

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