Coasting in neutral doesn't save gas

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So says Popular Mechanics:
http://www.popularmechanics.com/cars/how-to/repair/coasting-in-neutral-fuel-economy?click=pm_news
'Course the author is assuming an internal combustion engine. Presumably with a hybrid, the coasting actually CHARGES the batteries, thereby increasing gas mileage. I'm not even going to get into external combustion engines...
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Interesting, I didn't know about the injectors shutting off when coasting in gear. With a carbureted engine, you would save some, but it is much harder on the brakes. I had a motor home that wouldn't lock in low, it would just jump to 2nd no matter the selector position. That was downright scary in Colorado brake fade was a certainty, not so much if, as when. As soon as I got to the flat lands I pulled the valve body and put one in from a 4wd truck. then it would stay where you put it, and descending grades was almost fun.
On the other hand, with a standard trans, always coast into red lights on level ground. I'm going to idle in neutral with the clutch out, waiting for the light, so it sets up the maneuver nicely, it saves the throw out bearing.
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I dont buy it, it isnt a gasolene consumption issue, when coasting in gear the engine is not moving at idle speed, the extra rpms are a drag on the transmission and lower mpg, the trans also has more drag being in gear. He is only thinking gasolene not drivetrain friction loss.
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== Coasting in neutral has to be one of the more stupid ideas circulating. You are essentially losing control of your vehicle in a sense and the transmission has no effect on braking and brakes will have to be used more. For acceleration, one has to engage the clutch and shift to the desired gear or in an automatic shift to the desired "mode". Why complicate one's existence? The saving is insignificant at best. I doubt that any great number of drivers would even contemplate such a stupid maneuver.
==
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I like the sound of my engine so whenever possible I put it in neutral and red line the tach.
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LOL
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Then you cant Rev it and make it sound good
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wrote:

=Coasting in neutral has to be one of the more stupid ideas circulating. You are essentially losing control of your vehicle in a sense and the transmission has no effect on braking and brakes will have to be used more. For acceleration, one has to engage the clutch and shift to the desired gear or in an automatic shift to the desired "mode". Why complicate one's existence? The saving is insignificant at best. I doubt that any great number of drivers would even contemplate such a stupid maneuver.
It was a standard feature built into some older cars. You flipped a lever and "freewheeled" Whenever you weren't accelerating, it just coasted =
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== Massey-Ferguson made a few models of tractors that way. Our neighbor's girl was killed when one of these tractors descended a hill in "freewheel mode". Driving a heavy tractor with no engine breaking was one of the more stupid ideas to come up with in a while. That feature could be locked out but the girl forgot about it. Her husband had two young kids to raise on his own. ==
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wrote:

=Massey-Ferguson made a few models of tractors that way. Our neighbor's girl was killed when one of these tractors descended a hill in "freewheel mode". Driving a heavy tractor with no engine breaking was one of the more stupid ideas to come up with in a while. That feature could be locked out but the girl forgot about it. Her husband had two young kids to raise on his own.
I don't know any perceived advantage to having free wheeling on a tractor would be, but sadly it was ignorance not free wheeling that killed her. I've had tractors, skid steers, and all manner of engine driven equipment, all my life. Unless you know everything about the operation of the equipment, you've got no business touching it. =
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Roy wrote:

I'd have to see the spec's for that to believe it...
I don't know about M-F having any hand clutch models or not, but either that or the 2-speed power-shift w/ a neutral between is the only way I'm aware of that any tractor would have such a behavior. Since Ferguson wasn't folded into Massey-Harris until the early to mid-50s sometime, it would have had to been fairly modern to have been M-F branded and it "just does not compute". I'm thinking the story has been sanitized in the telling...
Have had several that did have hand clutches and Allis-Chalmers w/ the "Power Director" (their version of the 2-speed power-shift). Never seen any that would free-wheel unless shifted or clutch disengaged.
--
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You haven't seen 'em all!!!
The MF1100 (as well as the 135, 65, and 165, among others) had "Multipower" as an option. Built from 1964 to 1972. With the multi-power system there is one hydraulic clutch pack and also a ratchet type assembly. When in low multi the hydraulic clutch is dissengaged and the drive goes through a pair of gears into a ratchet clutch which takes the drive to the gearbox. There is no engine breaking in low multi because of the ratchet clutch. When you move the transmission to high multi it locks up the hydraulic clutch and the hydraulic clutch gear drives another gear. Because the drive is now turning faster than through the low-multi ratchet clutch, this now becomes a free-wheeling device. It is for this reason that there is engine breaking in high multi power, but no engine breaking in low multi power. This is also why if you are in high multi going up a hill and you depress the clutch pedal that whilst in gear no roll-back can occur because of the ratchet clutch. ie. both systems are locked together. The hydraulic multi-power clutch is not torque converter, but is merely a multi-plate hydraulically operated clutch pack. The good thing about this is that there is no loss of power through to the gearbox. The clutch is a conventional clutch and so is the 3 speed gearbox.
So now you have the whole story.
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On Jul 31, 7:38pm, snipped-for-privacy@snyder.on.ca wrote:

== I couldn't have said it better...thanks. ==
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wrote:

=I couldn't have said it better...thanks.
Here is the actual article:
How Does Massey Ferguson Multi Power Work We are often asked how the multi power system on models such as the Massey Ferguson 65, 135, 165 etc. works. What really seems to intrigue people is that the engine breaking system works when in high multi-power, but there is no engine breaking when in low multi-power...
With the multi-power system there is one hydraulic clutch pack and also a ratchet type assembly. When in low multi the hydraulic clutch is dissengaged and the drive goes through a pair of gears into a ratchet clutch which takes the drive to the gearbox. There is no engine breaking in low multi because of the ratchet clutch. When you move the transmission to high multi it locks up the hydraulic clutch and the hydraulic clutch gear drives another gear. Because the drive is now turning faster than through the low-multi ratchet clutch, this now becomes a free-wheeling device. It is for this reason that there is engine breaking in high multi power, but no engine breaking in low multi power. This is also why if you are in high multi going up a hill and you depress the clutch pedal that whilst in gear no roll-back can occur because of the ratchet clutch. ie. both systems are locked together. The hydraulic multi-power clutch is not torque converter, but is merely a multi-plate hydraulically operated clutch pack. The good thing about this is that there is no loss of power through to the gearbox. The clutch is a conventional clutch and so is the 3 speed gearbox.
=
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RBM wrote:

What was the advantage of freewheeling on a big tractor? I can understand the ratchet to keep it from rolling backwards, but surely they could have done that without the freewheeling.
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Tony wrote: ...

I see none; I found only the barest mention on the M-F site in the heritage section of the Multi-Power transmission and that was the following...

Sometimes one can find vintage sales literature on such features online but I haven't been able to so far in a relatively short time.
I had thought it was only a dual-speed arrangement similar to the A-C and others; have never run across a live animal of the type and wasn't aware of the free-wheeling nature of the design.
It seems, indeed, perilous in that mode w/ any grade and an implement in tow in particular out of ground for transport, say.
--
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wrote:

To make dual range and hillholder without freewheel in low would have required almost twice as much mechanism.
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snipped-for-privacy@snyder.on.ca wrote:

Interesting...I was not aware of that--there were virtually no Massey tractors ever in this area; they dominated the combine market for a while when the 90's came out but IH red, Deere green and Case orange were the only significant tractor varieties by the early 60s thru the merger wars w/ just a smattering of Allis, M-M and Oliver. Nuow there's Deere dominates in almost everything other than some specialty items.
I'll agree that's a seemingly worthless feature; can't see what it was intended to accomplish useful but certainly wouldn't be good in roading situation.
Grandad bought a little A-C WD45 when he was getting less able but still wanted something he could manage and a full line of the snap-coupler attachments. Since we had so much in the equipment, Dad traded up to a D-17 and I did a _lot_ of row crop work (milo sorghum) with it. It had the 2-speed power ranger w/ the disengaged section between shifting that occasionally would be the cause of trouble in a loaded condition if tried, particularly to shift up under heavy load. In low gear w/ load it might come to a complete halt and in our sandy conditions could then bounce and dig when engaged the high speed and then one had a mess in the field w/ a hole/hill...but it was always possible in a road situation to shift it in w/o needing to clutch so it wouldn't ever run away from you.
--
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One thing it accomplished was a "hill holder" in high range, and the second is an extremely easy to implement clutchless downshift.

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snipped-for-privacy@snyder.on.ca wrote:

It seems that the free-wheeling was a side effect of the design rather than a design feature, maybe. I'm sure it was somehow advertised as a boon although. :)
The A-C power-shifter accomplished the clutchless downshift as did several other variations (but w/o the hill holder, of course).
That would have had some value in some places but out here on the high plains it would have served no purpose as one would have to hunt really hard to find any hill upon which to practice. :)
--
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