Tailgate to save gas?
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Tailgate to save gas?
So I was watching Mythbusters and they were doing something that reminded me of a my days driving a pretty weak 85 Corolla wagon...
The car was by no means a power house anyway and by the time I got to driving it, it was pretty used up... It probably did 0-60 in about 20 seconds and in the open would barely hit 75 with the pedal to the medal (helped if there was a downhill and some tailwind).
This inability to keep up with freeway traffic ended up making me do something which in retrospect was pretty stupid... I tailgated big rigs all the time. We are talking 5 feet off the bumper kind of tailgating.
Doing this meant all I had to do was get up behind the trailer and suddenly the 75mph that would have required me to floor it only took a little light throttle to maintain.
At the time I wasn't thinking fuel efficiency, I was just thinking ease of driving, but drafting obviously does help mileage a lot. So I was wondering, I see people on here regularly reportinng 30+ mpg, for those of you getting good mileage, do you find yourself following cars pretty closely on the freeways?
The car was by no means a power house anyway and by the time I got to driving it, it was pretty used up... It probably did 0-60 in about 20 seconds and in the open would barely hit 75 with the pedal to the medal (helped if there was a downhill and some tailwind).
This inability to keep up with freeway traffic ended up making me do something which in retrospect was pretty stupid... I tailgated big rigs all the time. We are talking 5 feet off the bumper kind of tailgating.
Doing this meant all I had to do was get up behind the trailer and suddenly the 75mph that would have required me to floor it only took a little light throttle to maintain.
At the time I wasn't thinking fuel efficiency, I was just thinking ease of driving, but drafting obviously does help mileage a lot. So I was wondering, I see people on here regularly reportinng 30+ mpg, for those of you getting good mileage, do you find yourself following cars pretty closely on the freeways?
http://autos.yahoo.com/articles/auto...N0aW5nLWdhcw--
4. Bumper-buzzing
Tailgating is a bad move for many reasons. First of all, it's unsafe. You reduce your ability to react if the car in front of you slows or stops. It also means you have to pay ultra-close attention to that car which reduces your ability to scan for other hazards ahead of you and to the sides.
And tailgating wastes gas. Every time the driver ahead taps his brakes, you have to slow down even more than he did. (That's because you can't react immediately so you have to slow even more because you're slowing down later.) Then you accelerate again to get back up to speed and resume your bumper-buzzing routine.
Hang back and you'll be safer - plus you'll be able to drive more smoothly and use less fuel. A good rule of thumb is to allow two seconds of space between your car and the one ahead. You can figure that out by counting off two seconds after the car in front of you passes an obvious landmark like an overpass.
To an extent being behind a semi/car can help, but very minimally.
4. Bumper-buzzing
Tailgating is a bad move for many reasons. First of all, it's unsafe. You reduce your ability to react if the car in front of you slows or stops. It also means you have to pay ultra-close attention to that car which reduces your ability to scan for other hazards ahead of you and to the sides.
And tailgating wastes gas. Every time the driver ahead taps his brakes, you have to slow down even more than he did. (That's because you can't react immediately so you have to slow even more because you're slowing down later.) Then you accelerate again to get back up to speed and resume your bumper-buzzing routine.
Hang back and you'll be safer - plus you'll be able to drive more smoothly and use less fuel. A good rule of thumb is to allow two seconds of space between your car and the one ahead. You can figure that out by counting off two seconds after the car in front of you passes an obvious landmark like an overpass.
To an extent being behind a semi/car can help, but very minimally.
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Drafting behind a big truck is a legitimate technique. To the comment above about "wasting gas", you will actually save a lot of gas if you do it right. Drafting behind a semi is best suited to long interstate trips. However, you must be willing to drive kind of slow (at the truck speed limit) and you have to be prepared for a lot of rock chips. If you have a rental and you don't mind driving slow, then you can usually slot in behind a semi on a long trip and stay there for hours. On most rural interstate routes, there is rarely any reason to slow down or tap the brakes.
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While their warining is true it needs a grain of salt...
First off, for the most part a semi on a smooth running freeway with not too many exits will not be slowing down often or much. I can vouch that on the 101 I followed semis from Cotati to San Rafael (about 40 miles I would guess) many times and rarely had issue with having to slow down due to the trucker doing the same save a few regularly busy on ramps.
Now that said, I was going to have to slow down for those sections whether I was tailgating or not becuase they slowed traffic down across the board. Sure I might have had to panic slow more behind the semi, but it isn't quite as bad as they make it sound in the warning. And remember, your catch up will be done in the draft of a truck so it's not nearly as fuel consuminng as it would be in the open.
Then stack on top of that that I think I am probably above average at speed matching. One of the things I do pay careful attention to when driving is maintaining exact distance to the car in front of me evenly and smoothly (it's an OCD thing). And I would bet if you video taped my drivers view for an hour on the freeway you would suspect I somehow tied my cars throttle to the car in front of me baring really bad situations.
As for the reduction in reaction time I had a few ideas (which are probably flawed) but made me feel better about it at the time:
1: While you will have reduced reaction time, have you ever seen a big rig try to stop? It will take that big rig 3 times at least what it takes me to stop even with all his braking power. Given that I would think even counting for reaction time I could avoid slamming into the truck short of him running into an overpass support pillar or something.
Basically in most emergency stop situations I MIGHT tap the bumper of the semi during my reaction time, but if I stand on the brakes and so does the semi, I will start to brake faster than him and actually fall back even after initial contact (which would probably be a relative impact of 10mph or so at most sinnce he only just started braking a few feet ago).
2 There is something to be said for being attached to a huge semi truck sized bumper... In a crash situation it might end up being better to be touching the truck while it absorbed the crash and provided a huge crumple zone for your whole car rather than letting the truck 150 ft ahead of you reduce speed relative to you so much that you slam into it.
Think of a train running down the track. If it crashes every car immediately benefits from the car in front of it. However a fast moving trolly behind slamming into the now stopped train is going to be completely crushed.
3 It certainly does cut off your ability to concentrate on things around you but again you now have a huge semi truck sized bumper ahead of you and that is all you really have to worry about.
If a deer or ignorant driver swerves in front of you on the freeway there is a good chance you will slam into them or have to swerve so dramatcially you risk your safety otherwise. Behind a semi, likely they will just glance off the semi leaving you in a virtual safe zone...
Sort of...
Anyhow, circumstances certainly come into play, but I would think for the vast majority of drivers most of the time tailgating a semi would not result in a lot of uncessary hard braking and reaccelerating.
And remember even if you do brake harder than you need to, a semi trucks draft (even a mini vans draft) is probably good for 40-50 feet. At worst you aren't really in a functioning draft but you are in the turbulance which is still much easier than pushing through relatively still air; so even if you do have to reaccelerate, you will be doing so at much less air resistance than normal. So much so I would expect it would likely counteract quite a bit of any of your extra fuel burn.
Oh and the mythbusters recorded up to a 45% increase in fuel efficiency by tailgating a semi. That was just straight shot, no braking but still...
As for :
A good rule of thumb is to allow two seconds of space between your car and the one ahead.
That's solid advice excecpt... if you fall more than 1.5 seconds behind the car in front of you, someone will jump in your lane ahead of you!
First off, for the most part a semi on a smooth running freeway with not too many exits will not be slowing down often or much. I can vouch that on the 101 I followed semis from Cotati to San Rafael (about 40 miles I would guess) many times and rarely had issue with having to slow down due to the trucker doing the same save a few regularly busy on ramps.
Now that said, I was going to have to slow down for those sections whether I was tailgating or not becuase they slowed traffic down across the board. Sure I might have had to panic slow more behind the semi, but it isn't quite as bad as they make it sound in the warning. And remember, your catch up will be done in the draft of a truck so it's not nearly as fuel consuminng as it would be in the open.
Then stack on top of that that I think I am probably above average at speed matching. One of the things I do pay careful attention to when driving is maintaining exact distance to the car in front of me evenly and smoothly (it's an OCD thing). And I would bet if you video taped my drivers view for an hour on the freeway you would suspect I somehow tied my cars throttle to the car in front of me baring really bad situations.
As for the reduction in reaction time I had a few ideas (which are probably flawed) but made me feel better about it at the time:
1: While you will have reduced reaction time, have you ever seen a big rig try to stop? It will take that big rig 3 times at least what it takes me to stop even with all his braking power. Given that I would think even counting for reaction time I could avoid slamming into the truck short of him running into an overpass support pillar or something.
Basically in most emergency stop situations I MIGHT tap the bumper of the semi during my reaction time, but if I stand on the brakes and so does the semi, I will start to brake faster than him and actually fall back even after initial contact (which would probably be a relative impact of 10mph or so at most sinnce he only just started braking a few feet ago).
2 There is something to be said for being attached to a huge semi truck sized bumper... In a crash situation it might end up being better to be touching the truck while it absorbed the crash and provided a huge crumple zone for your whole car rather than letting the truck 150 ft ahead of you reduce speed relative to you so much that you slam into it.
Think of a train running down the track. If it crashes every car immediately benefits from the car in front of it. However a fast moving trolly behind slamming into the now stopped train is going to be completely crushed.
3 It certainly does cut off your ability to concentrate on things around you but again you now have a huge semi truck sized bumper ahead of you and that is all you really have to worry about.
If a deer or ignorant driver swerves in front of you on the freeway there is a good chance you will slam into them or have to swerve so dramatcially you risk your safety otherwise. Behind a semi, likely they will just glance off the semi leaving you in a virtual safe zone...
Sort of...
Anyhow, circumstances certainly come into play, but I would think for the vast majority of drivers most of the time tailgating a semi would not result in a lot of uncessary hard braking and reaccelerating.
And remember even if you do brake harder than you need to, a semi trucks draft (even a mini vans draft) is probably good for 40-50 feet. At worst you aren't really in a functioning draft but you are in the turbulance which is still much easier than pushing through relatively still air; so even if you do have to reaccelerate, you will be doing so at much less air resistance than normal. So much so I would expect it would likely counteract quite a bit of any of your extra fuel burn.
Oh and the mythbusters recorded up to a 45% increase in fuel efficiency by tailgating a semi. That was just straight shot, no braking but still...
As for :
A good rule of thumb is to allow two seconds of space between your car and the one ahead.
That's solid advice excecpt... if you fall more than 1.5 seconds behind the car in front of you, someone will jump in your lane ahead of you!
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Yeah, I wouldn't recommend this to people as a gas saving technique. But if someone wants to make their own call on it, that's up to them.
The big thing to remember is that regardless of your safety, you are probably ____ing off a truck driver getting in his blind spot. I would think the only graceful way to do this would be if you met a truck driver at a gas station or sommething and asked if he would mind you drafting him.
The big thing to remember is that regardless of your safety, you are probably ____ing off a truck driver getting in his blind spot. I would think the only graceful way to do this would be if you met a truck driver at a gas station or sommething and asked if he would mind you drafting him.
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Team Echo
Joined: May 2008
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From: Chicago, Illinois
I saw this mythbusters episode a long time ago. As a truck driver I have to say that this can be pretty dangerous. The truck can not see you at all. Many times the only way I can tell if someone is behind me is by the shadow their vehicle casts in the next lane. And while it may be true that "rarely" a truck brakes out on an open highway, there are 1000s of reasons that we do. It also completely blocks your view of the road ahead. In my truck I can unavoidably run over a giant gator (tiretread), carcass, muffler, and you can have zero time to avoid it. Lastly, a car rear ending a truck is one of the most deadly kinda of accidents. Ive seen fatality wrecks like this at least a dozen times in the past 3 years alone.
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Re: Tailgate to save gas?
Originally Posted by Devedander
So I was watching Mythbusters and they were doing something that reminded me of a my days driving a pretty weak 85 Corolla wagon...
The car was by no means a power house anyway and by the time I got to driving it, it was pretty used up... It probably did 0-60 in about 20 seconds and in the open would barely hit 75 with the pedal to the medal (helped if there was a downhill and some tailwind).
This inability to keep up with freeway traffic ended up making me do something which in retrospect was pretty stupid... I tailgated big rigs all the time. We are talking 5 feet off the bumper kind of tailgating.
Doing this meant all I had to do was get up behind the trailer and suddenly the 75mph that would have required me to floor it only took a little light throttle to maintain.
At the time I wasn't thinking fuel efficiency, I was just thinking ease of driving, but drafting obviously does help mileage a lot. So I was wondering, I see people on here regularly reportinng 30+ mpg, for those of you getting good mileage, do you find yourself following cars pretty closely on the freeways?
The car was by no means a power house anyway and by the time I got to driving it, it was pretty used up... It probably did 0-60 in about 20 seconds and in the open would barely hit 75 with the pedal to the medal (helped if there was a downhill and some tailwind).
This inability to keep up with freeway traffic ended up making me do something which in retrospect was pretty stupid... I tailgated big rigs all the time. We are talking 5 feet off the bumper kind of tailgating.
Doing this meant all I had to do was get up behind the trailer and suddenly the 75mph that would have required me to floor it only took a little light throttle to maintain.
At the time I wasn't thinking fuel efficiency, I was just thinking ease of driving, but drafting obviously does help mileage a lot. So I was wondering, I see people on here regularly reportinng 30+ mpg, for those of you getting good mileage, do you find yourself following cars pretty closely on the freeways?
All those gas savings go away when you rear-end somebody at 75mph.
I see a well worked-out rationale for why you're going to continue tailgating Semis and have convinced yourself it's safer than not tailgating them, because they act like some sort of huge personal "crush" zone, your own personal "pillow" to run into if you mess up.
My Dad, who drove for Coca Cola Enterprises for a long time, has had severe back problems for years since some idiot in a coupe ran into the back of his tractor trailer. The other driver had to be hospitalized immediately. You'd think the impact wouldn't translate, and it would just be absorbed by the trailer, right?
You are fooling yourself if you honestly believe anything you've said is true. And being uninformed, even ignorant about the actual driving situation you are in, you're going to go out there and put other people's lives in danger because you want to save a few dollars worth of gas while driving around.
If you think it takes a Tractor Trailer a long time to stop, sure it does. Unless you count JAKE brakes, or them running into something in front of them, or the cars in the lane on your left trapping you in the right lane, or any number of other driving situations that you can't predict.
The lack of personal responsibility and understanding here is nothing short of astonishing.
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Well first off, the mythbusters guys showed noteable results out 50 ft so not exactly up the tailpipes, and secondly, I did say those ideas were probably flawed somehow...
Probably mainly in that the rear bumper of a semi trailer doesn't seem properly positioned to do more than decapitate a car driver.
Anyhow... that was kind of a tangent, in general I was wondering if those here who get good gas mileage in general also do tailgate in general... it seems the two might corelate.
Probably mainly in that the rear bumper of a semi trailer doesn't seem properly positioned to do more than decapitate a car driver.
Anyhow... that was kind of a tangent, in general I was wondering if those here who get good gas mileage in general also do tailgate in general... it seems the two might corelate.
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Well I get great highway mileage, but I don't draft behind trucks because they are usually travelling too slow. I just try to maintain a constant speed. Cruise control helps with that. I also have a CAI and a grounding kit. I get over 400 miles from every tank now.
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DeepSouth Scions
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this is a completely stupid way to save gas, and im sure there are people dumb enough to try it. heres an idea, to save a little more on a tank im going to chip the ____ out of my car, then possibly risk an accident and insurance rates going up since it is all going to be your fault. I know the OP doesn't seem to condone this and realizes its a bad idea so no disrespect to you. Anyway, when I try to drive fuel efficient on the highway and when its nothing but highway best I have done is 28..and I don't follow to close to answer the question.
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This actually does work and very well. Open your windows or sunroof when you are behind a semi and then go into the other lane, you will feel the difference. For me personally, I live in an area where people cruise in the left lane and dont move over, so I just find a nice SUV or Minivan and tail the hell out of them for gas savings. They dont move over because they think theyre cops or something, but I'm saving MPG like a *****.
