First Road Trip - Disappointing Fuel Economy
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R320 CDI
First Road Trip - Disappointing Fuel Economy
Just got back from my first road trip from Pensacola, FL to Orlando, about 480 miles each way. I started out with about 2300 miles on my R320 CDI. I averaged just over 21 MPG going about 80-85 MPH on the way there and about 24 MPG on the way home. I admit, I have a bit of a lead foot, but I still thought I would do better than that. Will fuel economy improve significantly as the engine continues to break in?
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From: Dallas, Texas
R350 4-matic
Wow. I would have thought for sure the 320 would be way better even w/out break-in. I get 22-22.5 driving 75-80 on highway over 300+ miles.
Right now w/ gas prices what they are, this is when I don't wish I had got the R500.
Right now w/ gas prices what they are, this is when I don't wish I had got the R500.
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From: Scotland
2004 SL500, 2007 R350 Sport
I was beginning to wish I'd gone for the CDI but maybe not now if that mpg is normal. I'm getting 21-25 most tanks. Would have expected the CDI to have a good bit more.
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Add to that that in the DFW area it seems that diesel is 10-15% more expensive than gasoline and the mpg argument for the CDI is less/non-existent. The extra torque would be nice though. . .
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2004 SL500, 2007 R350 Sport
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From: a place
my car
actually, on the open road the 500 may not be greatly worse than your 350
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From: Toronto
2006 E320 CDi, 2008 3/4 Ton Suburban, 2007 "rice rickshaw" Accord 5 speed
weight + full time AWD = poor mileage
Just got back from my first road trip from Pensacola, FL to Orlando, about 480 miles each way. I started out with about 2300 miles on my R320 CDI. I averaged just over 21 MPG going about 80-85 MPH on the way there and about 24 MPG on the way home. I admit, I have a bit of a lead foot, but I still thought I would do better than that. Will fuel economy improve significantly as the engine continues to break in?
The R is not much under 5,000 pounds.
Full time all wheel drive.
Presumably you have the full 3 rows of seats filled with kids and their gear too?
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From: Toronto
2006 E320 CDi, 2008 3/4 Ton Suburban, 2007 "rice rickshaw" Accord 5 speed
good mileage compared with an SUV
My Suburban returns 16-19 mpg cruising on the highway, 13 mpg city so your R320 CDi is an economy car by comparison.
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R320 CDI
From what I understand, diesels take a while to break in. My next road trip will be over the holidays so I'm going to wait and see. I'm still getting about 480 miles between 20 gallon fill ups which is much better than my Acura MDX.
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From: Dallas, Texas
R350 4-matic
50 miles...that is more than just a little worse in my wallet.
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Joined: Apr 2004
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From: N. Illinois, USA
2021 GLS450, 2015 E250BT 4Matic, 2007 GL320CDI, 2005 SLK350, 2001 SLK320
My GL320CDI experienced a bump up in fuel economy at around 1K miles and another noticable improvement around 6k miles. I've heard that the fuel economy continues improving even up to and thru 10k miles on this engine.
Gas engines tend to hit their peak MPG a lot sooner. So it would make sense that a 350 gas engine may return same or better MPG than a 320CDI when both have only a couple thousand miles.
Gas engines tend to hit their peak MPG a lot sooner. So it would make sense that a 350 gas engine may return same or better MPG than a 320CDI when both have only a couple thousand miles.
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Mercedes Benz
Um, no. A guy in the neighborhood liked my R so much he traded his E350 in for an R500. On our golf trip to San Antonio from Austin and back he averaged 18.3 cruising at 75-80 on I-35. I mean it's not bad for a V-8, 'cause he gets almost 350 miles/tank. Meanwhile I get a little over 400 miles/tank.
50 miles...that is more than just a little worse in my wallet.
50 miles...that is more than just a little worse in my wallet.
That takes driver out of the equation. 1 mpg I go with the 500!
The 6 works very hard to keep the car moving.
Love my R350 but its not the quickest thing around.
