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1) Drafting: close behind

At highway speeds there's no doubt that driving close behind a large vehicle dramatically reduces fuel consumption.

This is not a recommended practice due to it being illegal in most areas. That being said you CAN draft without tailgating. If your local law says you must be 3 seconds behind the vehicle in front of you then stay 3 seconds behind the semi. You may not be getting the same benefit as true drafting, but it's better than nothing.


2) Find a 'blocker' for slower freeway speeds

Some people are uncomfortable driving at speeds less than the average flow of traffic on multi-lane freeways.

One solution is to find another vehicle going the speed you want to travel (large, conspicuous vehicles work particularly well) and drive either ahead of or behind it.


3) Close the sunroof at higher speeds

Some sunroof styles are better than others. The worst offenders are the kind which tilt and slide to the outside, on top of the roof. When open, these "roof-top spoilers" can significantly increase aerodynamic drag.


4) Reduce speed

Aerodynamic drag increases exponentially with speed, so reduce highway cruising speed as much as practical and safe.

Generally, a vehicle's most efficient speed is just after its highest gear has engaged.


5) Constant throttle position cruising

Once up to speed, pick a throttle position and hold it.

Advantages: more efficient than using the cruise control (which varies throttle position frequently and wastes fuel on hills).

Disadvantages: less efficient than "driving with load" (DWL) / "target driving" (where the throttle is eased on inclines).


6) Cruise control - when to use it

Set the cruise control if you're the type of driver whose speed creeps up higher and higher the longer you're on the road, or if you have difficulty holding a steady speed (it wanders up and down).

But realize that cruise control is just a band aid for those behaviors. Generally it's less efficient than constant throttle driving, and much less efficient than "driving with load" / "target driving".


7) Cruise control - when not to use it

Only use cruise control on flat roads. On hilly roads, cruise responds to changes in grade - by feeding in more throttle on the uphill and releasing on the descent - in the exact opposite way an efficient driver would.


8) The 'corridor effect'

All else being equal, traveling at a constant speed on a freeway within a flow of traffic (in the same direction) is more efficient than going the same speed in isolation. The reason is aerodynamic: a flow of traffic generates a localized wind current in the direction of travel. You will benefit from this artificial breeze.


9) Drive by the MPG DIC

Start out by getting your Cobalt to the cruzing speed you want. Then begin to let off the throttle while keeping track of your DIC set to INST MPG. You are looking for the max mpg you can get while staying at that speed on LEVEL road.

Once you find this "magic" mpg number stick with it. This means change your throttle position as many times as you need to in order to keep this mpg number the same or more. You will find after a while that you are pressing the throttle more when going downhill. This is where you pick up speed.

You will also find that in order to keep that mpg number the same you will be letting off the gas going uphill. Don't worry, you will get that speed back when you go down the other side.

NOTE: Before you go driving by the MPG DIC set a hard limit. This means that when you slow down below a speed you are comfortable with you give it more throttle to get back to your cruzing range. You will find that you really do not need to do this often. After all, no one wants to be rolling up an interstate at 45 mph.
 

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Nice tutorial, a lot could benefit from this, I do all these things except for the tailgating one, never knew about that, I can get up to 60 MPG on expressway, but of course, you all know that's coasting, u cant coast forever, If you would like to see your numbers get to 99 MPG, just drop into Neutral when on expressway, right after a MPG reset lol.

On average according to the MPG in Drive Info Center, I get 29.x MPG, I use street more than expressway though.
 

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I've always done like all of those. But when I drive long distance I just have to use my cruse control.
 

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Not justice...Punishment
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Write up? More like a copy and paste

but good tips nonetheless
Copy and paste is correct. Iz aint smarts nuff to bez ritin dat stuff...

Seriously, there are two of these complied from various internet sites, and adjusted to be Cobalt friendly. The first one says this, but I forgot to put it on this one.
 

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lol copied or not I like it still, I dont do too much highway driving but next time I do I'll remember this... most of my driving is lawless country roads where I get terrible mileage haha!

I've drafted before and it works really well... let the truckers do all the work haha!
 

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Using the MPG-DIC technique, my 2009 XFE sedan got 35 mpg on the last two tankfuls. I think the technique had a serious effect of around 2 mpg.

DIC was my last innovation. I had already switched to synthetic crankcase oil, wheels that are five pounds lighter/wheel, and modestly increased tire pressure. The tire pressure is 38 psi.

thanks for the tips
 

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My commute is 10.2 miles on the freeway and 3.8 miles of city streets. Seven traffic lights. I don't do a lot of freeway driving other than my commute.

Welcome to our forum, Fr3akazoid. I recall reading your writing on Ecomodder last year and I thought it was pretty insightful.
 

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Thanks Ecobalt.

If that is your route then your doing pretty good. Those lights got to be hurting you quite a bit. Can you ever time them or do you get forced to stop at most of them?

The freeway part of your comute could be limiting you quite a bit as well depending on if you get stuck in stop and go or if going any slower then 65 mph would get you run over.

Most of my trips are slow back roads which is great for mpg but when I do have to go into the city and face traffic and forced speeding I find it hard to get much better then 38 - 40 mpg.
 

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Almost all of my driving is in stop and go traffic. :( I live about 2.5 miles up a pretty steep hill with like 5 stop lights and a 1/4 mi of speedbumps at the very end so coming home kills me. But you'd think that it would get evened out by just being able to coast down the hill in the morning when I go to work. Nope! Stop and go traffic from my house ALL the way to my job! Then when I get off work, stop and go ALL the way to my giant hill. I average 26 mpgmost tanks :(
 

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very good tips... i find myself using the cruise control a lot mainly because i have a heavy right foot... but if im cruising in a pack of traffic i'll use the gas pedal and thats when i find i get the best mileage.


agita_san... have you thought about finding a different route home? it might take you a bit longer but finding a route with less lights and traffic might help you a lot!
 

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There really aren't any other options for me, only one road into my neigborhood and the freewya, even with traffic is the only real option for getting to and from work :(
 

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i feel your pain agita_san i live on a beach with one road that goes north and south with stop lights every 1/4 mile and heavy tourist traffic and no other options
 
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