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jimmiejoe
02-20-2013, 04:18 AM
Seems my fuel economy has jump and I am not sure why.
I was getting 18-18.7 MPG and a range of 360 miles each time I hit 0 on the fuel gauge until 1525 miles. Now I have hit 360 and still have between 3-4 on the fuel gauge.
The only things that are different on this tank are:
1) 50% at 65MPH and 50% at 55MPH instead of a top speed of 70.
2) climbed to 7000 feet instead of staying at sea level
3) added 600lbs over the rear axle to make sure I had traction in the mountains
4) possibly engine breaking has finally completed.

Any thought about which of these might be a factory in the better economy.

mikesprints
02-20-2013, 09:53 AM
I was getting 18-18.7 MPG and a range of 360 miles each time I hit 0 on the fuel gauge until 1525 miles. Now I have hit 360 and still have between 3-4 on the fuel gauge.
The only things that are different on this tank are:
1) 50% at 65MPH and 50% at 55MPH instead of a top speed of 70.


What are you meaning when you say you have 3-4, what gallons I assume? Sounds like another difference in your display vs earlier models. Mine has an analog fuel gauge, the computer estimates miles to empty.
How long on previous tank(s) were you at 70? Every mph over 55 takes exponentially more fuel.
You do have a 25g tank? @ just 18mpg your range should read at least 450 I would think.

My display is different somewhat. When I first got it 48k it would give me a "range" of 615 to empty. Yet of course it will go about 500. Just now, after 107k, I noticed it estimates 585 when I fill. Took it a long time to adjust to still an optimistic number. My overall avg is 20.7. I have a low roof though.

Your van is breaking in. I'ts learning how you drive. It doesn't have much of a baseline to avg. You went up to 7000 elevation. I can assume you had to come back down? That would have really pumped up the mileage range "guestimator".
Watch your "miles to empty" or "avg.mpg" on the SLS=since last start menu (if you have that one) the next time your doing a long downhill it will go waaaaaay up.

Enjoy that new ride!! :cheers: Is the front end different than the '12?

showkey
02-20-2013, 01:29 PM
Well it's a mystery:thinking:..............higher avg speed would hurt mileage so you slowed down that would help MPG, climbing with weight would hurt mileage,:thumbdown: so to get better consistent MPG would mean you slowed down more than climb if everything else stayed constant ( wind, temp, other driving techniques, tires, fuel, etc). Or your

OR coasting down the other side of the climb is off setting the climb with slower overall avg. speeds:thumbup:

OR someone is playing tricks on you adding fuel at night:bash::dripsarcasm:

david_42
02-20-2013, 01:53 PM
If #1 means you were going slower on this tank, that explains the difference entirely.

sailquik
02-20-2013, 02:25 PM
How many times did you manually downshift when pulling up the hills, or did you just stand on the throttle pedal and let the Sprinter
auto-downshift?
What is your rear end ratio? I don't see it in your data above.... is that the data from the window sales sticker?
Perhaps you need to get your full data card from your dealer at some point so you have "the rest of the story".
Running higher RPMs @ a lower speed can really get you some great mileage with the OM-642 3.0 V6.
Also, consider that your fuel flow is Zero (0) when you coast down hill, even if youi do not back off the throttle.
So if even 1/2 your mileage was down hill, and you slowed down or manually downshifted on the uphill grades that would give you
significant mileage improvement as the miles keep adding up, even as you are going downhill with zero fuel flow.
The low fuel light coming on @ ~ 360 miles is very normal.....that's @ about 20 gallons used.
You can actually go at least 100 miles further (between 460-500 miles) as there are > 6 gallons left in your 100 liter (26.4 gallons)
fuel tank. If you are getting close to 18 mpg then 6.4 gal. X 18 MPG = 115.2 miles.
I'm now consistently going to 450-460 miles with my 2012 hi-top/short-back 170" wb 3500 NCV3 and I still have a 1-2 gallons left in the tank when I
fill up. My average mileage (over pretty much the same route) lightly loaded is now 18.9 mpg with ~7,000 miles on the new Sprinter.
I drive it 320 miles on Thursdays and 320 miles back on Sunday evenings.
Roger

jimmiejoe
02-20-2013, 06:06 PM
What are you meaning when you say you have 3-4, what gallons I assume?the guage goes from 0 to 1 with 10 increments, each increment is about 2 gallons. 3-4 means 6-8 gallons still to go to 0 Sounds like another difference in your display vs earlier models. Mine has an analog fuel gauge, the computer estimates miles to empty.Guage is digital, no computer guessing as i only have the basic no frills computer.
How long on previous tank(s) were you at 70? probably 15-20 miles in each direction, so probably 2 trips meaning 60-80miles per tankEvery mph over 55 takes exponentially more fuel.
You do have a 25g tank? @ just 18mpg your range should read at least 450 I would think.I have previously run a diesel out of fuel going up and down the hills in Rhode island where the fuel is slashing from one end of the tank to the other, even though there was fuel in the tank. So I am a little nervous about dipping into the reserve on a brand new vehicle.

My display is different somewhat. When I first got it 48k it would give me a "range" of 615 to empty. Yet of course it will go about 500. Just now, after 107k, I noticed it estimates 585 when I fill. Took it a long time to adjust to still an optimistic number. My overall avg is 20.7. I have a low roof though.

Your van is breaking in. I'ts learning how you drive. It doesn't have much of a baseline to avg. You went up to 7000 elevation. I can assume you had to come back down? That would have really pumped up the mileage range "guestimator". No guestimator on mine.
Watch your "miles to empty" or "avg.mpg" on the SLS=since last start menu (if you have that one) the next time your doing a long downhill it will go waaaaaay up.

Enjoy that new ride!! :cheers: Is the front end different than the '12?
See above comments.

jimmiejoe
02-20-2013, 06:15 PM
How many times did you manually downshift when pulling up the hills, or did you just stand on the throttle pedal and let the Sprinter
auto-downshift?I just let the cruise control run the vehicle, and did not adjust the gears, just left it on D.
What is your rear end ratio?I believe i have a 3.XXX rearend I don't see it in your data above.... is that the data from the window sales sticker?Yes
Perhaps you need to get your full data card from your dealer at some point so you have "the rest of the story".
Running higher RPMs @ a lower speed can really get you some great mileage with the OM-642 3.0 V6.
Also, consider that your fuel flow is Zero (0) when you coast down hill, even if youi do not back off the throttle.
So if even 1/2 your mileage was down hill, and you slowed down or manually downshifted on the uphill grades that would give you
significant mileage improvement as the miles keep adding up, even as you are going downhill with zero fuel flow.I did start downshifting on the way down the hill to avoid using the brakes, and started to have some fun in the curves going down hill as well, since i was following two trailer towing vehicles with no passing i could not go very fast
The low fuel light coming on @ ~ 360 miles is very normal.....that's @ about 20 gallons used.
You can actually go at least 100 miles further (between 460-500 miles) as there are > 6 gallons left in your 100 liter (26.4 gallons)
fuel tank. If you are getting close to 18 mpg then 6.4 gal. X 18 MPG = 115.2 miles.
I'm now consistently going to 450-460 miles with my 2012 hi-top/short-back 170" wb 3500 NCV3 and I still have a 1-2 gallons left in the tank when I
fill up. My average mileage (over pretty much the same route) lightly loaded is now 18.9 mpg with ~7,000 miles on the new Sprinter.
I drive it 320 miles on Thursdays and 320 miles back on Sunday evenings.
RogerCurrently run about 90 out and 90miles back on the weekends but this time did 360 in one trip.

david_42
02-21-2013, 12:41 AM
Please stop with the green. It is unreadable.

sailquik
02-21-2013, 12:59 AM
jimmiejoe,
I know I will sound like a broken record here, but the addition of a ScanGauge II (or similar) performance monitoring gauge system would
go along ways toward giving you the information it seems like you wish to have.
% Engine LOD is the key PID, Gallons per hour (GPH is another really good PID, then digital RPM, and digital Speed.
That's what I run and I can check the Scan Gauge II and instantly tell what changes my engine management systems
are making.
It's definitely "good to know" these things.
Running along in overdrive (yes, your Sprinter in top (5th gear) is in OVERDRIVE (0.83:1 ratio) is OK at 70 mph, it's much less
OK @ 45-55 mph.
60 mph is about the break even point if you need more power as 5th gear with your 3.912 rear end will be 2200 RPM....not enough for
really good acceleration or when pushing through headwinds or with a load inside or behind your Sprinter.
A simple tap to the left on the shifter handle will bring you up to 2700 RPM....much better for both fuel economy and performance.
With the SG II you can check the fuel flow (GPH) and instantly see if the downshift helped your mileage or not. If not, tap the shifter to the
right and your back in overdrive.
The manual downshift can be used when you are in Cruise control also. If you try to make a manual shift that going to damage anything,
the TCM (Transmission Control Module) won't allow it. It's all programmed into the ECM and TCM!
Hope this helps,
Roger

Joe Jet
02-22-2013, 03:15 AM
7000'. at that altitude the air drag is significantly reduced, about 25%. Thats why airplanes cruise at higher altitudes....efficiency due to less drag. when you are cruising your sprinter the primary variables for the power required to maintain a constant speed are 1 air drag, 2 gravity/hills, and 3 the friction of the engine and drivetrain. since the second only varies to make the initial climb and the 3rd doesnt vary at all, unless youre driving in rain or snow, that leaves the air drag as the greatest variable with the altitude change. the other cool thing is turbocharging. a normally aspirated vehicle will lose a considerable amount of power with an increase in altitude, but the turbo compresses the air and can provide sea level or greater air pressures to the engine to maintain power output.

GregT
02-22-2013, 08:52 PM
Joe Jet is correct, I always get amazing mileage when driving in the higher elevations here in Colorado, sometimes 23+.