saving gas by following another car

Way back in the olden days, kids on roller skates would snag on to the back end of troller cars for fun.Sometimes, they would get some empty tin cans and some wire.They would snag one end of the wire on to the underground trolley car cables and watch those tin cans going around town.Some of the early trolley cars had a horse to pull the trolley car.There was a platform built on to the trolley cars.At the top of the hills, the horse would get a free ride going down the hills. Those were the Good old days. cuhulin

Driving 20 ft behind at speed isn't incompetent ? I accept it's only part of the full picture.

Graham

When you are traveling at speed and when you blink your eyes, you have traveled a lot of distance.That last eye blink could be dangerous.I always allow plenty of room for the vehicles in front of me. cuhulin

Damn, son, how old *ARE* you!?!?!?!

My age? I am sixty seven years old. About twelve years ago, I bought a softback book about Trolley cars.I read all about it in my Trolley cars book.Los Angeles used to have a fine Trolley cars system, untill that crooked Rockefella dude had their Trolley car system ripped out.There still are some American Trolley cars in operation, in South America. cuhulin

I just followed a truck at about 2 to 3 cars distance for 35 miles at a trip of 275 miles 2 weeks ago. The traffic was pretty light late in the night and that was the reason I dared to follow that close. I don't know how much it improved my mileage but I got 41.25 MPG at target speed of 65MPH for the trip.This is the highest MPG I got driving at that speed. I think it helps although I won't do that at busier traffic. My car is 1994 Camry 4 cyl.

Thought it may be of interest to someone.

That's not even close enough to get any benefit from the truck drafting you along. If anything, you probably lost a little due to the buffetting from being that far back from the truck. You got good mileage because you were going the speed of a truck for 275 miles (as opposed to the 75-80 most of us would be running late at night in light traffic).

I think "light traffic" is the key. Most of my daily driving is on the highway, but I generally get awful mileage because of a) heavy traffic, necessitating occasional speed adjustments and b) the fact that my car gets absolutely awful economy in town, so the small amount of non-highway driving that I do really drags the average down. Normally I get about 22-24 MPG but it can go over 30 if I can just get on a highway, set the cruise, and go... even at *higher* speeds than I usually travel during my morning commute.

I've noticed this effect on two different (but similar model) cars...

nate

miles at

late in

at

got

that at

When i was young and _________ (careless, stupid and crazed)

i **once** drafted a big rig when driving long distances.

I remember feeling and seeing a difference in my cars performance observing the tach and the feel of the car's movement while drafting etc...

*BUT* this drafting ease on my car's performance did not occur until (and this is where **STUPID** part comes in ) somewhere between 1/2 to 1 car length

And it may have only been the car was working so hard to get through the wind screen at the back of the truck that the car overcoming the resistance of that wind screen just felt like i was drafting and was not actually significantly drafting at all.

apparently this is a good way to kill yourself !

so, please don't be as careless as i was. yes, that ranks up there with the stupidist things done.

you were not imagining it. Mythbusters tested this to see how much benefit you would get from drafting a big rig and got the following results..

Without Drafting = 32 mpg

100 feet back = 35.5 mpg, an 11% increase 50 feet back = 38.5, a 20% increase (this would be perhaps what most people would view as "3 car lengths) 20 feet back = 40.5, a 27% increase (pretty close to 2 car lengths) 10 feet back = 44.5, a 39% increase 2 feet back, gas consumption actually increased but the gave no numbers. This appears to be the only time there is a wind buffeting effect.

They, of course, have disclaimers saying to stay at least 150' back so you aren't in the truckers blind spot. I don't see what difference that makes, there is nothing the trucker can do other then brake that would affect you so being in his blind spot seems like a pointless concern for this situation. the key is simply to be prepared to stop and having enough room to do so just as you would in any other situation. One advantage of drafting a big rig is that they don't have very good brakes compared to a "normal" vehicle so you don't need as much following distance to be able to stop without hitting them (they can't stop as fast as you can).

As one other poster mentioned, there could also be the benefit that drafting also makes you maintain a nice uniform, and probably slower then you otherwise would maintain, speed... which will also increase your mileage.

Great. Save $1 in gas. Pay $100 in additional risk. Do it 50 times and you're guaranteed to have wrecked the car.

If you do it on a motorcycle the sword cuts both ways -- (1) You're a little warmer because of the nice warm truck exhaust; (2) You're likely to pass out or at least get a real bitch of a headache if you breathe the nice warm truck exhaust too long.

Thanks for the advice. I just wanted to see if it made any difference. The reference MPG was 39MPG at a similar speed I had in another trip on the same highway. Not too much (I drafted only 35miles) but it adds up if you travel often. I had to drive at ~ 60MPH to get 42.xx MPG and this 41.25MPG is pretty nice at 65MPH (save me time).

As I said, I would only do it in very light traffic that there is no concern of sudden brake needed from the truck. Most of time, I avoid trucks ahead of me like a plague as they block my view of the traffic ahead of me. Realistically, it's very hard to find a truck to draft. They're either driving too fast or too slow for me. And some dislike people driving too close behind them (from reading on net).

Found it here:

_For_Money

I was probably ~50 feet. Since then, I've not had any opportunity to draft again. Safety is still more important.

Some?!?! Try ALL. Ever see those stickers on the back of the trailer saying 'If you can't see my mirrors, I can't see YOU!' ? They are there for a reason. If he has to lock it up due to a deer jumping in front of him or something, he'll barely feel you going splat on the back of his trailer. And the paperwork he will have to do will mess up his whole run schedule.

You can easily get some benefit and be perfectly safe. Most people who have a daily commute spend much of their time less then 50 feet from the vehicle ahead. It's no big deal.

The "Mythbusters" on the Discovery channeled tested this theory and found that it was true that you could reduce fuel consumption by drafting a big rig. The closer you drafted the greater the increase in fuel economy (and the greater the increase in danger of collision!). See:

Ed

Sort of like wrapping your phone line around a shortwave radio to see if that helps.I once tried that, I couldn't see/hear any difference at all. There is no way in heck I will try following a vehicle too close! cuhulin

Blinded by the Headlights. Road Kill.Food on the Table.Yum Yum. cuhulin