Hello - I have a 98 e300td with 157,000 miles and generally enjoyed 28-30 MPG. It dropped to about 25 and now it is in low 20s. I changed air filter, added fuel injector cleaner to gas but still have low mileage. I don't smell anything, nothing is leaking - any suggestions?

Has your gas station recently changed to the new LSD?

I note that it might contain ethanol ( maybe 15%) but I thought it was there for awhile. This is recent - would that explain it - this is pretty bad.

The change seems too extreme to be just attributed to USLD fuel.....
Check for a malfunctioning/siezed brake caliper....especially the rears. A dragging brake along with a fuel change to USLD may drop your mileage that much.
I am assuming that there are no other symtoms since you did not mention any rough idle or stalling out.
If it was a problem associated with electical or a fuel and air flow metering component (like a MAF sensor or Turbo relay) you would have had a malfunction message and code thrown. So check thoughs brakes.....

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FRED

Daily Driver: 98 E300TD 199K
Hobby Car: 69 Austin Mini
Past Diesels: 84 300SD, 312K
87 300SDL, 251K
94 Chev. K-1500 6.5Ltr.TD, 373K

Thanks for suggestion on brakes. I think they are ok - had them changed about 8 months ago - but I will check em out.

At present you are correct - no engine warning light - however for several months I did have a glow plug code ( replaced them) and one related to the relay. Recently the light went out - so I assume all is okay with electronics ( unless of course the warning system itself now has an issue - but I doubt.)

But yes it seems odd that such a signficant drop in such a short period of time - happened after I brought it to a mercedes dealer for change in front end bushings.

you think is there a chance that your odometer is turning slower than it used to?

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'85 300D Turbo - CA Version

Haven't checked my cars yet but my F250 diesel dropped from 23 to 17.7 to 18.3 MPG after filling up with ULSD. I've heard of other 250 owners who experienced the same thing. And yes, I fill up at the same station and drive the same as i always did. Only diff was ULSD.

Check these posts:new low sulpher diesel fuel

Cheers,

Bill

a few years back I changed from Michelin to Goodyear tires, and lost 4mpg overnight. I still have 10-15 thousand miles left on the Goodyear. Next set will be Michelin. At least the French can make good tires. Many years ago I had a Renualt R-10. Looking back, not too bad, but I beleive even that little gas 4 cyclinder 1100 engine can out run my 81 240D.

this 240D is the slowest thing I have ever driven. Except for 1 and 2 gear, all the other times I 'floor the gas pedal.'


Bob
1981 240D 4 speed manual

I drive mine like a fully loaded tractor/trailer.

And dread those high speed merges.

Cheers,

Bill

Wow! Bill, if people are really experiencing that much of a drop in diesel fuel effeciency using USLD then we have just lost the battle......our return on our investment just went down the toilet! There would be very little operating cost differential between a diesel vehicle and its gasoline version to give anyone the incentive to buy a diesel in the future.
That gives me more of an incentive to blend USLD with BioDiesel to bring the Cetane back up for improved mileage and performance.

__________________
FRED

Daily Driver: 98 E300TD 199K
Hobby Car: 69 Austin Mini
Past Diesels: 84 300SD, 312K
87 300SDL, 251K
94 Chev. K-1500 6.5Ltr.TD, 373K

I don't know about others, but I bought my 240D, just because it was a MB Diesel and no other real reason. I do know that as a general rule, any Diesel will out live a gas of the same size, vintage. So, a longer engine of a Diesel is just the icing on the cake for me.

Bob 1981 240D

Sorry, I get all wound up when good intended government regulation (ULSD), which is suppose to improve exhaust emissions are offset by the increase in the consumption of fuel.....where does that make any sense?
I can understand where you are coming from with your vintage 240D. Three out of 4 diesels I have owned were Mercedes. I bought them because of their effeciency and durability..... and it just so happens Mercedes makes the best diesels sedans for my type of travels. I use them for business....they are my "work horse" and mobile office. The cost of being on the road is my biggist expense....and it eats up my bottom line when fuel costs go up and or efficiency of the vehicle goes down or I get to the point of no-return on repairs. At that point I might as well throw a lit railroad flare in the back seat.. walk away.....and "go sell ties in Tahiti or something"

__________________
FRED

Daily Driver: 98 E300TD 199K
Hobby Car: 69 Austin Mini
Past Diesels: 84 300SD, 312K
87 300SDL, 251K
94 Chev. K-1500 6.5Ltr.TD, 373K

I don't know about everybody else, I am just reporting what I have experienced.

ULSD is the only change. I drive the same roads, the same speed, the same distance, etc. etc. and after 3 checks of the mileage it has consistently been in the range previously described. LOW!

Wouldn't you know that i sold my only gasser last summer and now gas here is at $2.45 and still dropping.

Cheers,

Bill

Bill it may be worth trying fuel from different refineries. Even with the old fuel there are certain brands I stay away from as they seem to go through the engine like mouthwash. As fate would have it the best consistant milage on the old fuel was obtained by a brand that generally has a reputation of problems with their gas. But their diesel is good. Up to 20 percent or so apparent milage drop was observed with one other brand. Irving fuel only available in north east quadrant of states was the good brand by the way. I do not know if that fuel is coming out of the canadian refinery for the american stations or not though. I wonder if the heavy truckers have already established the brands that are better. Must ask some truck drivers I know the next time I see them. If experiences with all brands are simular we might have to use biodiesel as was mentioned to get some semblance of milage back. I think your experiences so far will probably be common unfortunatly. At least with certain engines if not all. But hope not. Any injection pump leaks yet? I really hope that is not going to become a real problem with everyone as well. Some reports have indicated it might. I would also have preffered to see ravings of excess milage on the new fuel but life does not seem to work like that usually.

No. I haven't had any IP leaks. I continue to use PS additive from Wally's.

Sure, I understand about different brands give different results. The brand that I have cinsistently gotten 23 MPG is the same brand and same station that I got 5 MPG less. Maybe I'll have to switch brands to see if it makes a difference. Problem with that is my usual brand is currently $2.69 and the other stations charge $2.85.

Cheers,

Bill