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I realize that appears to be an oxymoron, but I've been playing around with some things I saw on a hypermiling website and some of them appear to work.. Most are common sense, but I was never used to trying to drive this way..
My commute is 8 miles one way, it's 4 miles of open interstate (the predominent traffic flow is in the opposite direction of my travels) and 4 miles of suburban streets with congestion, un-synchronized stoplights, crowded rush hour etc..
My combined mileage on the commute: "before" was 13.5 mpg, "after" is 17.8 mpg. A good day might be 18.5, if I'm lucky. I measure the mileage using the Commanders' mpg guage, I reset it every morning. 4.3 mpg doesn't sound like much, but it's a 31% increase from my old way of driving.
Some of the techniques are:
1. Slow down: I now usually drive about 56 on the interstate instead of the old keeping up with traffic at 75.
2. I always use cruise control on the interstate.
3. When I exit, I coast in neutral with the engine on, (I understand you can damage a modern automatic by coasting at speed with the engine off), from the time I hit the exit ramp until I reach the light at the bottom of the ramp.
4. I coast a lot when driving in town.. I will get up to speed, and whenever the traffic looks like it might backup, I throw it in neutral and coast until the traffic clears. The idea is to use the brakes as little as possible.
5. When the traffic light goes red up ahead, I coast up to the light instead of driving up then braking.
6. Pull through a parking space instead of simply pulling in. You can leave much quicker than backing out, you'll use less fuel.
7. When stopped, I stay in neutral until it's time to go. If you're stopped in gear, the engine is still trying to move the car against the brakes.
8. Avoid sitting and idling. I will even shut the engine off if I know the light will be red for more than about 30 seconds.
9. I now try really hard to time the lights so I can avoid complete stops. Really difficult around here as the lights are unsynchronized.

Some of the things the hardcore hypermilers are advocating are downright dangerous, i.e., drafting other drivers, "pulse and glide" where they will accelerate to say 60 on an interstate then coast down to around 40-45 (sometimes slower) then repeat, driving too slow for the road they're on, stop signs are "optional", etc...
 

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Man thats a practice I am unsure about. I am not sure but I think coasting in neutral is against the law in most states and creates a unnecessary danger. Even though I would love to save gas I don't think some of these practices are the ones we should be doing.

Now mind you I am all about slowing down, pulling through a parking space when it is a option.

I know its hard to enforce the coasting laws but do you want to be the one who shoots his RPMs up to 9k when he has to move out of the way quickly? I don't.
 

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A 31% increase is definitely nice. I'm getting around 17 mpg with 90% highway. I drive 68 mph on the highway which is extremely painful (just like penguin says, I also enjoy passing people). With a 38 mile trip to work, I'm getting killed at the pump. It's still cheaper for me to pay for gas than to get a "beater" that gets good mileage.

Has it been verified that coasting to a stop light in neutral is more fuel efficient than coasting in gear?
 

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I will caution people though about coasing in neutral. When you put your vehicle in neutral at speed, it is possible for the torque converter to lock up and basically have the same effect as slamming the tranny into Park. I've seen it happen, granted the vehicle was doing in excess of 100mph at the end of a drag race, but something to be mindful of. You're probably ok at 60- but I'm not sure where the cutoff is.

Oh, and I've never once heard, or seen in a state drivers test booklet that it is illegal to coast. I think someone is making stuff up here.
 

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I am starting to notice people turning off their engines at red lights.
 

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I've read and seen studies done before that turning off the engine for only a few seconds/minutes, only to fire it up again later... actually uses more gas than just sitting idle for the same time.

My gas saving? I just don't move the dang thing. Take the Patriot wherever/whenever I can. Ha.
 

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I agree with almost everything billspringer says. Except the coasting in neutral and shutting off the engine at a light. I have done both but do not like to. Coasting in neutral has to cause some tranny issues when droping it back into drive at speed. Coasting in drive only raises the RPM slightly from being in neutral and with the throttle totally closed can it really use up much more fuel?
Shutting off the motor at a light can't really save much. I like the Heat and AC, and worry that if I shut it off it won't start, etc...I guess it depends how long the light is though, and I do it at RR crossings while waiting for a train, etc. I think my Hemi uses less than a half gallon an hour at an idle. At least that's what I remember from sleeping in it overnight last winter....
I think all the other stuff is right on!
 

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RedCommander said:
Oh, and I've never once heard, or seen in a state drivers test booklet that it is illegal to coast. I think someone is making stuff up here.
Coasting Prohibited; Violation As Civil Infraction - Mich. Comp. Laws Section 257.678

I 21710 Coasting, in neutral on downgrade. California

Section 32-5A-57. Coasting down a hill in Alabama with your car in neutral is illegal. Alabama

Do I need to find more? Let me know! ;)
 

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I think the added wear and tear on parts would out weigh the cost you might save on gas. The starter, transmission, ignition, and so on would have a serious decrease in life span if you turn your car off everytime you stop at a red light or drop it in neutral. Think about how many times you start the car on a normal basis and then add number of red lights you stop at during your typical day.
 

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M3racer said:
I think the added wear and tear on parts would out weigh the cost you might save on gas. The starter, transmission, ignition, and so on would have a serious decrease in life span if you turn your car off everytime you stop at a red light or drop it in neutral. Think about how many times you start the car on a normal basis and then add number of red lights you stop at during your typical day.
DING DING!!!!
 

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Discussion Starter #13
The trick with shutting the engine off at a light is to only shut it off when you know you're going to be stopped for more than 30 seconds.. Around here, when you're at a cross street to a main drag, if the light goes red just as you pull up, you're sitting for 90 to 150 seconds before you get the green again, the priority is to the main road. I only have two intersections where I could possibly shut down for the red, and that's only when I know it'll be a long light. Plus I don't usually have the bad luck to get BOTH long reds..
As far as the coasting goes, I generally put the engine back in gear after I stop. As far as safety goes, I don't see much of a difference between what I do and someone who pushes in the clutch and costs down the exit ramp. Instead of keeping my foot on the clutch pedal, I keep my hand on the shifter...
Now there are some things the hard core people do that I'm not going to do... Turning off the A/C in the summer is one!!!
In any case, I forgot to include the link to one of the sites on my original post, this is 100 tips for gas mileage: http://ecomodder.com/forum/EM-hypermiling-driving-tips-ecodriving.php
Some of the stuff they mention is just plain dangerous, but most of it's pretty interesting..
 

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AKFossil said:
Coasting Prohibited; Violation As Civil Infraction - Mich. Comp. Laws Section 257.678

I 21710 Coasting, in neutral on downgrade. California

Section 32-5A-57. Coasting down a hill in Alabama with your car in neutral is illegal. Alabama

Do I need to find more? Let me know! ;)

Well dangblamnit goldurnit, he's right:

California vehicle code

Coasting Prohibited

21710. The driver of a motor vehicle when traveling on down grade upon any highway shall not coast with the gears of such vehicle in neutral.

http://www.dmv.ca.gov/pubs/vctop/d11/vc21710.htm

I have fun doing this on my motorcycle.
 

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I spent about a month and several tanks of gas religiously trying most of these things, including cruise, coasting, and keeping RPMs < 2000 as much as possible. My driving is all suburban (no highway, no city, just inconsistent stop/go and all below 50). Previously over two years I averaged 12.0. My best tank using these methods improved only to 12.9. Maybe it would be more impactful if I had some highway driving in there, but for me it's not worth it. I also became very concerned about shifting back into drive at speed, especially at lower speeds (~20mph) as the transmission would "clunk" back into gear. That can't be good. So I've gone back to my regular driving habits and found a different way to save gas - carpooling to work (much more effective at saving money and gas than any hypermiling!)
 

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Another danger in coasting is that it allows you to roll further forward if accidently struck from the rear by another vehicle which could cause additional damage to your vehicle as well as the one in front of you.
 

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Wow,,if only I had an 8 mile commute,,,,but then again I love the rural area I live in! The one good thing is that 75% or more of my driving is state highway where the MDS kicks in & I'm on 4 cylinders. Where it really sucks the gas is when I run around in city traffic, which is maybe 15-25% of the time. But all in all I average about 17.5 with everything. The one thing I am considering is converting the air intake that I understand can both increase horsepower & gas milage. (plus I hear that it sounds cool,,,lol).

Still for a 5K pound vehicle that can seat 7 & has pleanty of "get up & go" when you need/want it, or tow a heavy load with power to spare, I can't complain. Just a joy to drive!
 

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NMRealtor, good to hear from you again, it has been awhile.
 
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