Improving MPG - E300 Turbodiesel
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 18
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'16 E250 BlueTec 4MATIC
Improving MPG - E300 Turbodiesel
Hi -
Just drove my newly-purchased 99 E300 Turbodiesel back to California from NY. MPG with air conditioning and speed around 75 averaged just under 30 - I was expecting more. Just once - driving at night with A/C in economy mode - I averaged 33 on a single tank.
I was expecting slightly better MPGs, given comments I've seen here and in other groups. Anyone have ideas as to what to look into and/or tune up to make the car a bit more fuel-efficient?
Everything else seems great - I was quite impressed with the power of the car. Takes off like a rocket for passing, and I didn't come across a single hill or pass on the entire trip that the car didn't shoot up with power to spare.
Thanks...
Just drove my newly-purchased 99 E300 Turbodiesel back to California from NY. MPG with air conditioning and speed around 75 averaged just under 30 - I was expecting more. Just once - driving at night with A/C in economy mode - I averaged 33 on a single tank.
I was expecting slightly better MPGs, given comments I've seen here and in other groups. Anyone have ideas as to what to look into and/or tune up to make the car a bit more fuel-efficient?
Everything else seems great - I was quite impressed with the power of the car. Takes off like a rocket for passing, and I didn't come across a single hill or pass on the entire trip that the car didn't shoot up with power to spare.
Thanks...
Super Member
Joined: Sep 2003
Posts: 783
Likes: 1
From: Murrieta, Southern California
Late Built 2005 W-211 E-320 CDI
Truthfully Stated!
Originally Posted by bmisf
Hi -
Just drove my newly-purchased 99 E300 Turbodiesel back to California from NY. MPG with air conditioning and speed around 75 averaged just under 30 - I was expecting more. Just once - driving at night with A/C in economy mode - I averaged 33 on a single tank.
I was expecting slightly better MPGs, given comments I've seen here and in other groups. Anyone have ideas as to what to look into and/or tune up to make the car a bit more fuel-efficient?
Just drove my newly-purchased 99 E300 Turbodiesel back to California from NY. MPG with air conditioning and speed around 75 averaged just under 30 - I was expecting more. Just once - driving at night with A/C in economy mode - I averaged 33 on a single tank.
I was expecting slightly better MPGs, given comments I've seen here and in other groups. Anyone have ideas as to what to look into and/or tune up to make the car a bit more fuel-efficient?
This is what happens when individuals comment and like to "bend" the truth just a little!
What you have experienced mirrors my our own!
Anyone that tells you differently is not telling the truth, or is driving like a lttle old lady.
We have logged over 27K miles in the year that we've had ours, and that is what they do get.
EPA was listed at 26 city and 36 highway.
The only way one can get 36 mpg highway is to not use the A/C and keep the speed down below 65 mph.
Have you noticed how the T/C never locks up?
Thats one reason for poor fuel mileage. You cannot get good mileage with power being used to heat tranny fluid.
Evidently MBZ was more concerned with "smoothness" than fuel economy when they left out this modern feature.
Funny thing is that the new W-211 CDIs do have locking torque convertors that work and the cars do operate smoothly,
even though their motors are more powerful by more than 50 percent, fuel economy is even higher at 27/37.
(Torque on the '99 E-300 is 240 ft/lb; Torque for the '05 E-320 CDI is 369 ft/lb, or 30 ft/lb more than the E-500!)
I believe that this increase in fuel economy is because of the operating locking T/C and the taller differential gears.
(2.65 vs 3.07)
Where in California are you now?
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 18
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'16 E250 BlueTec 4MATIC
Hah! That'll teach me to believe everything I read online 
My manual transmission 190D did occasionally get to 40 mpg, but usually averaged in the low-to-mid 30s, so I'm not shocked that the E300 gets the mileage you're stating and I experienced.
I did notice that the transmission seemed greatly confused by the hills in San Francisco (where I live) when I took it on them for the first time last night. Lots of shifting and racing; guess I'll have to learn to adjust my style to it a bit, and would agree with your assessment of the effects of lack of locking and shorter gear ratios.
Thanks,
Steve
My manual transmission 190D did occasionally get to 40 mpg, but usually averaged in the low-to-mid 30s, so I'm not shocked that the E300 gets the mileage you're stating and I experienced.
I did notice that the transmission seemed greatly confused by the hills in San Francisco (where I live) when I took it on them for the first time last night. Lots of shifting and racing; guess I'll have to learn to adjust my style to it a bit, and would agree with your assessment of the effects of lack of locking and shorter gear ratios.
Thanks,
Steve
Super Member
Joined: Sep 2003
Posts: 783
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From: Murrieta, Southern California
Late Built 2005 W-211 E-320 CDI
MY of the 190D?
Originally Posted by bmisf
My manual transmission 190D did occasionally get to 40 mpg, but usually averaged in the low-to-mid 30s, so I'm not shocked that the E300 gets the mileage you're stating and I experienced.
I did notice that the transmission seemed greatly confused by the hills in San Francisco (where I live) when I took it on them for the first time last night. Lots of shifting and racing; guess I'll have to learn to adjust my style to it a bit, and would agree with your assessment of the effects of lack of locking and shorter gear ratios.
I did notice that the transmission seemed greatly confused by the hills in San Francisco (where I live) when I took it on them for the first time last night. Lots of shifting and racing; guess I'll have to learn to adjust my style to it a bit, and would agree with your assessment of the effects of lack of locking and shorter gear ratios.
Was the 190D a "baby" 2.2 or a turbo 2.5? Standard tranny or automatic?
Try manually shifting the tranny in your E-300 TD as I do. Seems to help a little.
Thread Starter
Junior Member
Joined: Aug 2004
Posts: 18
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'16 E250 BlueTec 4MATIC
Originally Posted by Green E-300 DT
Was the 190D a "baby" 2.2 or a turbo 2.5? Standard tranny or automatic?
Try manually shifting the tranny in your E-300 TD as I do. Seems to help a little.
I did try manual shifting with the E300 on the drive back, but just for engine braking (twice on some steep downhills, just curious to see) - maybe I'll play with manual shifting a bit more with fuel economy in mind (though it's probably more trouble than it's worth). Thanks for the tip, though.
Super Member
Joined: Sep 2004
Posts: 551
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From: Virginia
2005 Carlsson CD32 E320 CDI Inline-6
Best I ever got so far with the CDI is 32 MPG
On a short 120 mile trip, A/C on, 3 passengers, 65 MPH or so with hills and a couple stoplights.
My all-around average is about 23 MPG, not great but not bad for a leadfoot in a 4000 lb car.
KB
My all-around average is about 23 MPG, not great but not bad for a leadfoot in a 4000 lb car.
KB
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Joined: Oct 2002
Posts: 1,560
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From: Columbia, SC
E300
Originally Posted by cdiken
On a short 120 mile trip, A/C on, 3 passengers, 65 MPH or so with hills and a couple stoplights.
My all-around average is about 23 MPG, not great but not bad for a leadfoot in a 4000 lb car.
KB
My all-around average is about 23 MPG, not great but not bad for a leadfoot in a 4000 lb car.
KB
