Fuel economy just keeps getting better!!!
Thread Starter
Super Member
Joined: Mar 2008
Posts: 903
Likes: 23
From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
Fuel economy just keeps getting better!!!
This is a little drive I took this afternoon:
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
Super Member
Joined: Apr 2008
Posts: 635
Likes: 2
From: Cali
2011 GL450
This is a little drive I took this afternoon:
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
MBWorld Fanatic!
Joined: May 2007
Posts: 2,244
Likes: 1
From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
This is a little drive I took this afternoon:
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
STP
MBWorld Fanatic!
Joined: Feb 2007
Posts: 2,548
Likes: 3
From: LA LA Land
'07 GL 450, '02 S 80 T6
Originally Posted by MomsBenz
I was pleased with our road trip I averaged 21.2 mpg in the 450 with the cargo carrier on top! Not too bad
Super Member
Joined: Apr 2008
Posts: 635
Likes: 2
From: Cali
2011 GL450
Junior Member
Joined: May 2008
Posts: 63
Likes: 0
C220
This is a little drive I took this afternoon:
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
This was a cross town drive on surface streets with stoplights, and a short, 3 exit burst on an expressway. Picture taken just before reaching my destination.
Stats: 23 km, 21 minutes, Average speed, 65 Km/h, fuel economy 9.1l/100km,
or 24.8mpg (us gal) 31mpg (imp gal).
Sorry about the pic, it's from my phone...
The new one I test drove a while back showed 12.2L/100 KM over a day's driving in the city. Your mileage is much better than that. Perhaps it is the KM`s on your vehicle. How many have you racked up since you got you GL
Trending Topics
MB World Stories
The Best of Mercedes & AMG
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Thread Starter
Super Member
Joined: Mar 2008
Posts: 903
Likes: 23
From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
I have been watching this like a hawk, and I have noticed that going up hills or idling when the engine is still cold, and blasting the A/C seem to have the largest negative impacts on mpg. I know that day in and out i will get 20% better ecomomy when I go to my parent's house up a gentle incline, than to my sister-in-law's place that is at a lower elevation, but up two steep hills....
MBWorld Fanatic!
Joined: Sep 2005
Posts: 6,192
Likes: 242
From: Albuquerque
'10 CL550, '12 GL550
I have been watching this like a hawk, and I have noticed that going up hills or idling when the engine is still cold, and blasting the A/C seem to have the largest negative impacts on mpg. I know that day in and out i will get 20% better ecomomy when I go to my parent's house up a gentle incline, than to my sister-in-law's place that is at a lower elevation, but up two steep hills....
Got in a tailwind once in NE New Mexico and saw 29mpg on the dash while going 70. A few miles on, the wind had shifted a little more to the side and the number dropped to 23.
Pulled a trailer with motorcycle from NM to south TX and each fillup produced poorer mileage, I assume because as we lost altitude we were punching through "thicker" air. The engine electronics should adjust for the different air density but it can't change the amount of work the engine has to do.
Banned
Joined: Feb 2008
Posts: 164
Likes: 0
From: Columbus, OH
2008 GL 320 CDI
I averaged 22-23mpg with a cargo carrier on top during a recent road trip, with flat, straight highway driving all the way.
Thread Starter
Super Member
Joined: Mar 2008
Posts: 903
Likes: 23
From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
Not in the city, man.
Yeah, but you get a denser charge, and more power per unit from the motor...
Yeah, but you get a denser charge, and more power per unit from the motor...
MBWorld Fanatic!
Joined: Sep 2005
Posts: 6,192
Likes: 242
From: Albuquerque
'10 CL550, '12 GL550
Super Member
Joined: Aug 2007
Posts: 603
Likes: 0
From: Spicewood, TX
2008 GL 320, 2007 Silverado LTZ C3500 Duramax Turbo Diesel
Density Altitude is the key. As the moisture and/or temperature goes up, the air becomes lighter. You would think that moist air would weigh more than dry air but not so. Very humid and hot air has a very high "density altitude".
An NHRA race in Houston can have a density altitude as high as a race in Denver, if the conditions are right (cool and dry in Denver vs very hot and humid in Houston) even though there's a 5000 VF difference.
An NHRA race in Houston can have a density altitude as high as a race in Denver, if the conditions are right (cool and dry in Denver vs very hot and humid in Houston) even though there's a 5000 VF difference.
Thread Starter
Super Member
Joined: Mar 2008
Posts: 903
Likes: 23
From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
Pressure is not density.
You are 100% correct, but we have an intercooler that should fix the temp issue after the charge heats up from the turbo. A few degrees of ambient is nothing compared to the cooling that takes place overall. That's the point I was making to Ikcris, the turbo makes the pressure, in our case variable with vanes, and not only related to exhaust pressure, but the intercooler creates the density. He's likely right, in that altitude did not help him, but thinking this through, it likely was not the culprit either. As I said earlier, I have noticed that a blasting thermatic/thermotronic has a huge impact on the CDI so that's what I would look at going from NM to Tex....
Your milage may vary.
Density Altitude is the key. As the moisture and/or temperature goes up, the air becomes lighter. You would think that moist air would weigh more than dry air but not so. Very humid and hot air has a very high "density altitude".
An NHRA race in Houston can have a density altitude as high as a race in Denver, if the conditions are right (cool and dry in Denver vs very hot and humid in Houston) even though there's a 5000 VF difference.
An NHRA race in Houston can have a density altitude as high as a race in Denver, if the conditions are right (cool and dry in Denver vs very hot and humid in Houston) even though there's a 5000 VF difference.
Your milage may vary.
Last edited by Brocktoon; Aug 6, 2008 at 10:04 AM.
MBWorld Fanatic!
Joined: Sep 2005
Posts: 6,192
Likes: 242
From: Albuquerque
'10 CL550, '12 GL550
The bottom line is that the fuel-air mixture is precisely controlled by the engine components and electronics and does not vary with altitude. The car burns more fuel at lower altitude because it is working harder and it takes more fuel to do more work.
MBWorld Fanatic!
Joined: May 2007
Posts: 2,244
Likes: 1
From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
I don't know if the same principles apply to the diesel engines but I do know that one name for turbocharging in aircraft is "turbo-normalizing" or "normalization," the purpose of which is to give the same power to the engine at higher density altitudes (whether due to temperature, atmospheric pressure and dew point or actually being at a higher altitude) as it would get at a lower altitude, usually benchmarked at sea level on a standard day. For instance, in a turbocharged Cessna 182 I flew, I was able to maintain the same power to the engine from ~1500 feet (Scottsdale airpark) to I think 12,000 feet. This did not mean, however, there was no detriment to performance - the prop's still pulling through the air and that (as Kent pointed out) was thinner at altitude. In fact, the amount of the effect is noticeable as low as 5000 feet, though not huge.
Just my two bits on the subject!
Just my two bits on the subject!
Thread Starter
Super Member
Joined: Mar 2008
Posts: 903
Likes: 23
From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
I don't know if the same principles apply to the diesel engines but I do know that one name for turbocharging in aircraft is "turbo-normalizing" or "normalization," the purpose of which is to give the same power to the engine at higher density altitudes (whether due to temperature, atmospheric pressure and dew point or actually being at a higher altitude) as it would get at a lower altitude, usually benchmarked at sea level on a standard day. For instance, in a turbocharged Cessna 182 I flew, I was able to maintain the same power to the engine from ~1500 feet (Scottsdale airpark) to I think 12,000 feet. This did not mean, however, there was no detriment to performance - the prop's still pulling through the air and that (as Kent pointed out) was thinner at altitude. In fact, the amount of the effect is noticeable as low as 5000 feet, though not huge.
Just my two bits on the subject!
Just my two bits on the subject!
MBWorld Fanatic!
Joined: May 2007
Posts: 2,244
Likes: 1
From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
Super Member
Joined: Aug 2007
Posts: 603
Likes: 0
From: Spicewood, TX
2008 GL 320, 2007 Silverado LTZ C3500 Duramax Turbo Diesel
You make more power at sea level, unless the water grains and temperature offset it, giving it a Density Altitude say equivalent to Denver. This is an ongoing concern for NHRA dragsters. Pomona, CA usually has the lowest density altitude in the country and that's where most of the records are set. There are other races near sea level, Houston and Gainesville, FL, but they have much higher density altitudes due to high humidity.
