Hey all,
Just got back from a long (3918kms or 2434mi) camping trip throughout western Canada. For those that don't know this is quite mountainous terrain.
Overall we consumed 785 litres (or 207 gallons) of fuel. According to my calculations this works out to an overall average of 11.75 MPG.
The wierd thing I have questions about is how on earth I managed to get best and worst MPG figures. My best tanks tended to be over very big mountain passes!! If anyone knows the area, we got 14.35MPG going over the Coquihalla, and 13MPG going over the Salmo-Creston pass in southern BC. These two passes are extremely long (30+kms?) and you gain quite a bit of altitude, somewhere around 1700 metres or 5500 feet! I drive up the hills usually out of OD, RPM usually around 2300, which pegs me around the 50 MPH range.
Now the worst tanks were amazingly on flat ground, these tanks were usually in the low to mid 11 MPG range. I usually drive at around 70 MPH, approx 2000 RPM, with no cruise on. My absolute worst tank this trip was my last one, totally flat country but with the cruise on at 70MPH, ended up getting 10.33MPG [img]/ubbthreads/images/graemlins/frown.gif[/img]
I tried a tank or two driving at 60MPH and found that it didn't make all that much difference. [img]/ubbthreads/images/graemlins/confused.gif[/img]
Oh yeah, the truck and trailer are below in my sig, the trailer probably weighed in just over 5000#, and the truck box was about 1/2 full with camping junk, etc, probably another 300# or so. Oh yes, tires were inflated to 55psi and TT was 35psi.
So, my question to the experts is, what is the best way to drive when towing in order to optimize MPG? When I tried it didn't work, when I thought I'd get bad mileage I ended up getting "decent".
Thanks in advance, here's a shot from Mt. Robson, the highest point in the Canadian Rockies....
I'm going to agree with "02PSD4ME". The absolute best mileage I ever got was 18.5 while driving through the mountains (Blue Ridge Parkway). I was unloaded, driving 45 mpg with overdrive off, and never had to stop and start off again. I'd drive this way all the time but I would get run over (aka - killed dead) on the expressways going to work everyday.
Joe
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2002 F350, Crew Cab, 4WD, ISSOPRO Gauges,
3.73, Auto, 2wd low range mod, No door dinger,
Interior lights off switch, Zoodad Mod,
Extra Trans Cooler, Before coolers trans fltr,
Coolant fltr, Crimestopper remote start/alarm
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My personal thoughts on this is At higher altitude you use lees fuel because the engine leans out because of thinner air. I used to live in Salt Lake and everytime we went to Chicago adn back on I-80 I noticed the samethng also.
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99.5 F-250 7.3 NVK3 Auto Trans CC XLT 4X4 Short Bed 3.73 Limited Slip
Experienced the same thing in my 85. My assumption was that when going up a grade such as you described, the fuel economy is poor, when coming down the other side the motor is just not working, little fuel is burned and the average economy really climbs. Best I can do with the 85 is 25 MPG on the flat, as high as 29 in mountainous areas.
Rick
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I was only wrong once, that was when I thought I was wrong, but wasn't.
85 F-250 4x4 6.9 Regular cab, 4 spd, flat deck 538 000k, 3.54 gears, making 25.5 MPG Imperial, Racor Water Fuel/separator, original owner.
95 F-350 XL 4x4, 7.3L PowerStroke, 5 spd, 4.10 LS 265/75R16, Regular cab, 246,000 miles, custom box, 12,000 Warn winch, replaced down pipe, home made air intake
72 Mustang Mach 1, original owner, Boss 351, 53,000 miles, estimated 425 HP, all go and still makes 18 MPG
74 F-350, 2x4 390 FE bored to 410, auto, 3.54 gears, 110,000 miles, original owner.
I just made a trip to Alaska and back during July about 9000 miles. My best mileage was when I used Exxon diesel in Canada. I got 1.5 to 2 mpg better with Exxon than I did with any other brand. It didn't seem to matter if I was in the mountains or the prairie I got different mpg with different brands of fuel. I did keep a log of all my fuel stops and averaged 11.75 mpg with the trailer in tow at 60-65mph most of the way.I don't know why exxon was better but I wish I could have used it the entire trip. [img]/ubbthreads/images/graemlins/shrug.gif[/img]
I think I used about every brand there was in canada. I converted the litres to gallons and calculated each tank of fuel. I also calculated the mpg for the entire 4100 miles from PA to Alaska. I noticed better performance with the exxon so I decided to see if the mpg was better and it was. I don't know why. I left the trailer in Alaska so I couldn't get as good a test on the way back running empty but the truck still seemed to run better on the Canadian exxon than it did on any other brand. I also ran a lot slower through the mountains which I am sure helped the mpg on the return trip. I wish I would have had the time to take a month to drive through the mountains,to much to see and not enough time!
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I left the trailer in Alaska so I couldn't get as good a test on the way back running empty but the truck still seemed to run better on the Canadian exxon than it did on any other brand. I also ran a lot slower through the mountains which I am sure helped the mpg on the return trip. I wish I would have had the time to take a month to drive through the mountains,to much to see and not enough time!
[/ QUOTE ]Good to know. The Canadian Rockies kind of make the Allegheny Mountains look like little hills IMHO.
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2002 F350 Lariat CC 4x4 Auto 4.10 DRW, DP-Tuner F5 live tuned stock, quiet, 40dd, 40, 60, 80 tow, 80e and 120r, B&W GN, BrakeSmart, 'pooned tank, tank and pre-pump mods, 2µ Dahl 100 filter, regulated return, BTS dual HPOP, AC singles with EDM 34 lpm nozzles, AIS, H2e, Spearco 6.0 IC, Hypermax 3.5" dp--> MBRP 4" 304SS exhaust, BTS tranny, 203º T-stat, Chevron ELC, coolant filter, Oilguard bypass with Schaeffer 9000, WranglerNW 200 amp alternator & Optima group 31 batteries, Nippon-Denso starter, SPA gauges, SteveRacer mods, Hella 80/100W 9007s, Hella Micro DE foglights, 1000FF driving lights, 220W backup lights, Stancor contactor, Michelin XPS Traction tires, X-Springs, Bilstein shox, custom bumpers but otherwise stock. Nov 30 '99 build engine with 16 K miles, Fluidampr, Comp Cam 910 springs, Melling LPOP and ARP headstuds. Alien-Patrol Customer Service Sucks!
Thanks for the replies guys, making sense so far. The one thing I forgot to add was even though you are going slower than you typically would on flat ground, wouldn't the higher RPM combined with the load pulling uphill contribute to lower MPG?
But on the other hand the downhill argument is really valid! If you go up 20 miles, you're usually coming down about the same... so if you get 7-8mpg on the way up you might get closer to 20 on the way down... evening stuff out I guess!
I just went through a similar trip in Ontario Canada, travelling 7162 kms over 2 and a half months. I burned a total of 1156 litres of fuel.
That translates into 14.6 MPG calculated using US Gallons.
My driving was mostly towing and some hilly parts over the Lake Superior section. My non-towing driving was mostly in town and subject to stop and go, idling, etc. I ran the A/c almost continuously.
The costs of diesel ranged from 84.9 cents per litre to 94.9.
I dunno if that's great MPG or not, but compared to what I've been seeing from you guys, its not bad.
PeterL
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1999 Ford F250 Supercab 2Wd Powerstroke, Line - X, Fumoto Oil Drain valve.
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My personal thought on this is: At higher altitude you use lees fuel because the engine leans out because of thinner air. I used to live in Salt Lake and everytime we went to Chicago and back on I-80 I noticed the same thing also.
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Diesel engines run lean all of the time, except when they're pedal-to-the-metal. More than 100:1 air:fuel ratio is common at idle.
One of the things high altitude/low ambient air pressure does is reduce the exhaust backpressure and the pumping losses. It's cooler at altitude, so the air conditioner's duty cycle is less - if you're running it at all - and it's cooling less-dense air. And most of all, running at high altitude reduces aerodynamic drag in a big way.
Between sea level and 2000 m, you're down almost 20% in air density and aerodynamic drag. Go to 4000 m and lose another 20%.
That's where a lot of the savings came from. Airplane pilots know this - you don't see 'em cruising around at a 5,000 foot altitude unless it's a very short trip.
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Douglas Campbell [drcampbell ot engineer dat kahm]
November 5, 2008: The fat lady sang. Back to actually working for a living.
1986 Isuzu P'up, 177,673.8 miles. Hella headlights, (highly recommended) DOT C-2 back end. (also recommended) R-12 air conditioner converted to R-406a. 4.1:1 rear axle converted to 3.4:1.
9/22/2007, age 21: Still running well when reluctantly sent away for reincarnation, due to body & frame rust.
Just got back from 6,000 mile trip from Florida to Colorado & back. (3,300 miles towing, and 2,700 non-towing. First tow with my 05 6.0. Strong puller. My overall tow mileage was 10.1 mpg. Not real tickled about that, but that's a topic for another thread. Pulling 8,500 lb 5th. We spent 3 days driving thru Colo mountains w/out the trailer, and stayed in motels for a couple of nights. My mileage average was 21. I have done this several times with my Dodge Cummins auto, and averaged 22-23. The Dodge averaged 20-21 at lower altitudes and on the flats. So, I agree about the higher mileage in the mountains. But as for going slower, I'm not real sure about that. It's bound to help, but I ran I-70 from Denver to Rifle and parts of I-25 at 70 mph, and was still getting better mileage than at lower altitudes.
[img]/ubbthreads/images/graemlins/shrug.gif[/img]
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2005 F-250 CC SB Lariat, 6.0 PSD, 5sp auto, 2wd, SRW, TowCommand, 3.73 LS Rear, Tow/Camper Pkg.
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