First long trip in $800 300 D 23 MPG is that good? - Page 3 - PeachParts Mercedes-Benz Forum

300sdlguy · #31 01-06-2006, 11:40 AM

Quote:

Originally Posted by Craig

Well, you're really comparing apples and oranges. A well tuned 617 will get mileage in the mid to high 20s depending on driving conditions. I agree 23 is on the low side, but anything over 30 is unrealistic. We are talking about 25 year old engine technology. BTW, a 300D only weighs about 300 pounds less than you SDL.

WOW, only 300 pounds less?

Also, I wasn't really "comparing" my 1998 Suburban with a 1981 300D. I DO realized then engine must have some technical advancements, but then again, my less technically advanced 6.2 diesel in my 24 year old 1982 Chevy Suburban that weights 6500 lbs and shaped like a brick still gets 25 mpg on the freeway, but only 20 if I drive above 80 mpg.

I have not owned a 300D, my comment was more about my shock at the low MPG that should be expected.

SO the 86-87 603 engine that much more technologically advanced in it's design and exectution than that of a 617 in a 1981????

#32 01-07-2006, 08:03 PM

Quote:

Originally Posted by 300sdlguy

WOW, only 300 pounds less?

Also, I wasn't really "comparing" my 1998 Suburban with a 1981 300D. I DO realized then engine must have some technical advancements, but then again, my less technically advanced 6.2 diesel in my 24 year old 1982 Chevy Suburban that weights 6500 lbs and shaped like a brick still gets 25 mpg on the freeway, but only 20 if I drive above 80 mpg.

I have not owned a 300D, my comment was more about my shock at the low MPG that should be expected.

SO the 86-87 603 engine that much more technologically advanced in it's design and exectution than that of a 617 in a 1981????

My understanding is the SDL is 3800+ pounds and the 300D is 3500+ pounds. The W123s are pretty solid.

http://home.hiwaay.net/~gbf/mbmodels.html

The 617 is a pretty primitive design, it's been around since 1975 and it's basically the same as the 616 (1973), which isn't much different from the 615 (1968), etc. I don't know the original roots of the design, but it's been around for a while.

Hatterasguy · #33 01-07-2006, 09:47 PM

Quote:

Originally Posted by 300sdlguy

SO the 86-87 603 engine that much more technologically advanced in it's design and exectution than that of a 617 in a 1981????

Yes, the 617 was the last of the old style diesels. The 603's were the first in a series of new diesels MB made. Look at an I6 CDI, not all that different then a 603.

They are different animals, apples and oranges comparison.

t walgamuth · #34 01-07-2006, 10:57 PM

with a 6.2 that would get over 18. but i didnt have overdrive on my turbo 400 tranny.

tom w

boneheaddoctor · #35 01-08-2006, 11:18 AM

Quote:

Originally Posted by t walgamuth

with a 6.2 that would get over 18. but i didnt have overdrive on my turbo 400 tranny.

tom w

I have 4.10 gears in my 3/4 ton GMC Sierra 4X4...with a TH-400 trans...no Overdrive and I get 14 mpg hauling about 8K pounds...the most I have hauled any distance.