my E300D (95') is getting approx 27-29 mpg, mostly freeway driving with 50% AC running. I don't know if it's out of tune or something. It doesn't smoke much, runs pretty smooth with about 205K miles.

Any ideas? Not too sure what's in a diesel tuneup......

Check the simple stuff first, then the more complex/costly:

• Tire Pressures, personally I'm at least 5 over the suggested.
• Wheel Bearing Status
• Fuel filters - Main & Pre-filter recently replace
• Air filter too
• Proper oil change, synthetic here
• EGR/intake cleaned?
• Transmission Fluid/Filter
• Rear Differential fluid changed
• Type of fuel - Higher percentage of BioDiesel, lower mileage
• Limit A/C as needed - sounds like you are doing this
• Injection Timing?
• Injector Status - Tested, rebuilt/replaced?
• Driving habits go without saying
• Speed also factor

Seems like their are others with your model that are getting better, but that is fairly subjective and subject to wide variations. I've been doing too much city and short runs lately and am in the mid 20's I guess

Other will certainly add comments and some obvious misses of mine.

__________________
raMBow

1999 E300DT Obsydian Black Metallic, Heated Full Leather Parchment options, E2, K2, 136,000+, best 36.5 mpg - GP's 12-04 & 11-12 Zero Stuck
2010 Honda Odyssey - The BrideMobile - best 26.5
(2) 2005 Honday Accord- (1 -Corporate 1 - Personal) - 110,000 4-cyl 30mpg
2000 VW Golf GLS TDI, Upsolute Chip (sold to Brother, now 300+k on it) 48.5 mpg like clock work
1987 Honda CRX HF - Sold 87,000 always over 50 mpg Max 67 mpg

On my diesels, when the mileage drops I start at the filters - air and fuel. Keep in mind, your mileage may be normal. I get 30mpg or so on the highway in the Texas heat cruising at 80+. In the city, 26 is about right. When the temps go down, the mpg goes up.

__________________
- Brian


1989 500SEL Euro
1966 250SE Cabriolet
1958 BMW Isetta 600

I get 30 on the highway at best 27 to 28 in town. My wife gets a little better inthe 97. Like everyone else check the basics first. If your mileage is consistant then it may be as good as it gets. has there been a change in your mileage?

__________________
Keith Schuster
2006 E350 98K miles
2013 Ford Explorer 15K miles

I used to get around 32MPG a few tanks ago.

I did some of the easy stuff recommended in the post above, I am going to do the rest.


Inlet manifold and EGR valve, how do you clean those?
thanks

I have a 95 with 222k on it - I get 32-33 on a highway cruise (80mph, AC on), and around 30 for normal driving (mix highway and city, AC on) in North Carolina (hot/humid summers).

I always use synthetic oil (I like Amzoil) - makes a difference (at least in my mind). Also, I always throw in some diesel fuel additive to help ensure injectors/lines stay clean, add some lube, eliminate water, etc. The minor additional cost doesn't bother me - I'm more interested in longevity of the car...

__________________
1995 E300D - 225,000 miles - White Exterior, Grey Interior - original owner