shocked a guy with true 240 fuel economy - Page 4 - PeachParts Mercedes-Benz Forum

DieselPaul · #46 07-10-2014, 01:08 PM

My dads 83 240D auto is getting like 24 with the AC on, and 28 with it off. He drives 75 on the highway. His 85 300D was returning slightly better.

barry12345 · #47 07-10-2014, 01:10 PM

Quote:

Originally Posted by Skippy

I had a 240D manual. Worst one tank mpg was 17. Best was 28. Typical was 22 or 23. My 300D always got better, even when it was still an automatic. I've just touched 30 on long highway trips, but right around 25 is what I get on most tanks.

For a time I drove a '90 International Paystar 5000 with a 14 liter Cummins making all of 350 horsepower and pulling a 32 cubic meter end dump. I never hit the scales with it (no scale houses in the country I was in), but I estimated the loaded weight to be about 130,000 lbs, with an unloaded weight more like 34,000. Upon further reflection I think both of those estimates are low. I checked the mileage a couple times and found I was getting 3 mpg loaded and 6 unloaded.

On the 240ds with manual transmissions there always seemed to me to be two general milage claims. This depending on the individual cars.

One claim is about 25 miles per gallon highway observed by some. The other claims seems to be about thirty miles per gallon highway.. This discrepancy has always bothered me as it was posted too many times to ignore. I did not suspect the many members quotes where fabrications.

It may be just driving style but I think it is something else perhaps unknown. To me the five miles per gallon difference claimed by many still disturbs me with the 616.

I have watched for any common denominator without any luck so far. I do not think the 617 300ds display this issue or disparity nearly as much .

I do believe in doing a comprehensive tune up on the 240ds because of this though. Unless you are around thirty miles per gallon already. Also some 240ds seem more powerful than others by a seat of the pants feeling. I have observed this issues presence over at least five years now.

Even though the 300d 617 turbo versions are heavier. The turbo seems to increase fuel efficiency. Add in that 617s are all automatics they are noticeably more efficient with that turbo. The non turboed 617s are not very fuel efficient in comparison with much less power available. Part of it is the higher ratio rear end of course the non turbo versions use.

JimFreeh · #48 07-10-2014, 01:12 PM

Quote:

Originally Posted by barry12345

On the 240ds with manual transmissions there always seemed to me to be two general milage claims. This depending on the individual cars.

One claim is about 25 miles per gallon highway observed by some. The other claims seems to be about thirty miles per gallon highway.. This discrepancy has always bothered me as it was posted too many times to ignore. I did not suspect the many members quotes where fabrications.

It may be just driving style but I think it is something else perhaps unknown. To me the five miles per gallon difference claimed by many still disturbs me.

I have watched for any common denominator without any luck so far. I do not think the 617 300ds display this issue or disparity nearly as much .

I do believe in doing a comprehensive tune up on the 240ds because of this though. Unless you are around thirty miles per gallon already. Also some 240ds seem more powerful than others by a seat of the pants feeling. I have observed this issues presence over at least five years now.

Proper accelerator linkage setup can make quite a difference in performance.

Jim

DieselPaul · #49 07-10-2014, 01:52 PM

Any 61x I've ever bought had the valves way out of spec. In 2014 most people could not tell you what a valve adjustment is.

Low compression on all cylinders will hurt power a bit, and with 64-71hp, you don't have much you can stand to lose.

JB3 · #50 07-10-2014, 02:24 PM

Quote:

Originally Posted by barry12345

On the 240ds with manual transmissions there always seemed to me to be two general milage claims. This depending on the individual cars.

One claim is about 25 miles per gallon highway observed by some. The other claims seems to be about thirty miles per gallon highway.. This discrepancy has always bothered me as it was posted too many times to ignore. I did not suspect the many members quotes where fabrications.

It may be just driving style but I think it is something else perhaps unknown. To me the five miles per gallon difference claimed by many still disturbs me with the 616.

I have watched for any common denominator without any luck so far. I do not think the 617 300ds display this issue or disparity nearly as much .

I do believe in doing a comprehensive tune up on the 240ds because of this though. Unless you are around thirty miles per gallon already. Also some 240ds seem more powerful than others by a seat of the pants feeling. I have observed this issues presence over at least five years now.

Even though the 300d 617 turbo versions are heavier. The turbo seems to increase fuel efficiency. Add in that 617s are all automatics they are noticeably more efficient with that turbo. The non turboed 617s are not very fuel efficient in comparison with much less power available. Part of it is the higher ratio rear end of course the non turbo versions use.

could be lead food syndrome. I floor my 240 everywhere and leave it long in gear so I can appreciate diesel noise. If im not roaring along at 75 or 80 whenever possible to lumber up to, im not a happy camper.

every hill im losing speed, so I go fast when I can. Plus there is nothing so fun as driving a slow car fast. If someone were to maintain 55 to 60 in a 240, economy driving would probably explain the difference in fuel accounts.

JamesDean · #51 07-10-2014, 04:12 PM

My 91 300D will get between 31-36 MPG. It could probably do higher if I went slower too. AND I HAVE DATA! Wooo

tjts1 · #52 07-10-2014, 04:34 PM

Quote:

Originally Posted by JamesDean

My 91 300D will get between 31-36 MPG. It could probably do higher if I went slower too. AND I HAVE DATA! Wooo

Which is completely within the realm of reality and no reasonable person would ever question it. As opposed to someone claiming 48.3mpg because "the trip computer said so therefore it must be true".

TimFreeh · #53 07-10-2014, 09:48 PM

Quote:

Originally Posted by tjts1

Which is completely within the realm of reality and no reasonable person would ever question it. As opposed to someone claiming 48.3mpg because "the trip computer said so therefore it must be true".

I noticed you put quotes around the 'the trip computer said so therefore it must be true"...... can you show me where someone, EXCEPT YOU, actually said that anywhere in this thread? Why do you continue to advance this absurd straw-man argument?

I was looking at the EPA estimates for mileage for the CDI and your 300D, it would appear that the figures are 27MPG for your 300D and 37MPG for the CDI. How come when you claim 38MPG and "back it up with Fuelly" were all supposed to agree its a 'reasonable claim' but when several CDI owners report getting 10 MPG above their EPA estimates, and don't base the number on the computer display, we're all supposed to mock them and laugh?

TimFreeh · #54 07-10-2014, 09:54 PM

Quote:

Originally Posted by JamesDean

My 91 300D will get between 31-36 MPG. It could probably do higher if I went slower too. AND I HAVE DATA! Wooo

Well maybe you do have the data.... but don't forget the data doesn't exist unless its been entered into 'fuelly'. At that point it apparently becomes it verified and validated.

With all that as a backdrop I'll go out on a limb and say that I had a 300D 2.5 turbo for 7 years as a daily driver and I got exactly the same mileage range you are experiencing.

jake12tech · #55 07-10-2014, 10:07 PM

Here's my take on this thread!

JamesDean · #56 07-10-2014, 11:21 PM

Quote:

Originally Posted by TimFreeh

Well maybe you do have the data.... but don't forget the data doesn't exist unless its been entered into 'fuelly'. At that point it apparently becomes it verified and validated.

With all that as a backdrop I'll go out on a limb and say that I had a 300D 2.5 turbo for 7 years as a daily driver and I got exactly the same mileage range you are experiencing.

BEHOLD THE DATA.

Always fill up until the pump clicks!

tjts1 · #57 07-11-2014, 01:34 AM

Quote:

Originally Posted by jake12tech

Here's my take on this thread!

Quote:

Originally Posted by JamesDean

BEHOLD THE DATA.

Always fill up until the pump clicks!

Data is beautiful. This is how its done.

Stugist · #58 07-11-2014, 02:25 AM

My 240D manual gets a pretty decent 24-27 MPG usually. I generally do a full engine tune-up (valves, purge, etc) twice a year; once before the cold weather sets in (where I also switch to 10w-40) and once when Spring sets it. Change filters as I go, or at either of these marks. These really help; the engine is getting up there in years and still has some kick to it, but it's really starting to show its wear in blow-by and cold starts.

For me, the kicker is fuel quality around here. I try to stabilize it with a variety of things (DieselKleen, 2-cycle, LiquiMoly, etc) and so far it's been working. However, even my normal stops will leave me with a fuel supply that only gets me 350, 375 miles. Usually I have to stop in around the 400, 450-mile mark.

Try to keep my driving consistent; 25-mile round trip for work every day plus at least one 50~ mile trip each week to where ever, plus normal within-town stuff.

I will admit, though, that my numbers are a rough guesstimate. The 240D has about an 18-gallon fuel tank. I don't drive her until the light comes on but usually till the last tick mark, so I base it off that I'm using about 13-15 gallons. I'll also take into account how many gallons actually get put in at the next fill-up (till the nozzle clicks).

Quote:

On the 240ds with manual transmissions there always seemed to me to be two general mileage claims. This depending on the individual cars.

One claim is about 25 miles per gallon highway observed by some. The other claims seems to be about thirty miles per gallon highway.. This discrepancy has always bothered me as it was posted too many times to ignore. I did not suspect the many members quotes where fabrications.

It may be just driving style but I think it is something else perhaps unknown. To me the five miles per gallon difference claimed by many still disturbs me with the 616.

I have watched for any common denominator without any luck so far. I do not think the 617 300ds display this issue or disparity nearly as much .

I do believe in doing a comprehensive tune up on the 240ds because of this though. Unless you are around thirty miles per gallon already. Also some 240ds seem more powerful than others by a seat of the pants feeling. I have observed this issues presence over at least five years now.

Even though the 300d 617 turbo versions are heavier. The turbo seems to increase fuel efficiency. Add in that 617s are all automatics they are noticeably more efficient with that turbo. The non turboed 617s are not very fuel efficient in comparison with much less power available. Part of it is the higher ratio rear end of course the non turbo versions use.

On the OM616, it REALLY just depends on engine wear. A nice, well driven and maintained 240D with an excellent engine (rebuilt or tediously maintained) will get almost 30 MPG, and I can confirm this through experience. Once you get a bit of wear in there, they tend to drop and stay around 23-26MPG, given that the engine is still being somewhat maintained and cared for. The fact that 240D owners also tend to use them as town cars and not take them on long-ish freeway runs to work-out the engines once in a while is, I think, a factor too.

Most people I've seen with 240Ds around here either like to keep them as garage queens or run them as daily around-towners. They're reliable little buggers.