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hydraulic lifter crew
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my 3/4 ton rides rough enough without pumping the tires up to the max.
i would need new kidneys, which would negate any fuel savings.

:rof
 

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Lets try this

Among Thomas' techniques is "pulse and glide" in which he accelerates and then coasts with the engine off until around 15 mph when he kicks the engine back on and accelerates again. "It's the automotive equivalent of skateboarding," he said.
:peelout
 

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Discussion Starter #4
Lets try this

:peelout
That brings up a good question. I do allow my vehicles to coast when it is advantageous. If I am on a mild descent I pop it into neutral all the time. As long as it doesn't increase or decrease velocity significantly.

So the question is: on an auto tranny is there any harm to be popping it into neutral and back in drive on the fly? The truck does this extremely smoothly (even more than my Toyota minivan). But I have often wondered if it has adverse effects. Cooling issues?
 

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Washington Chapter Vice President
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Shouldnt have any issues putting it in neutral. As far as shutting the engine on and off, I have never heard a more ridiculous statement. You are gonna wear the starter out and burn more fuel turning it on and off inbetween. At idle these trucks dont use a ton of fuel.
 

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Discussion Starter #6
Shouldnt have any issues putting it in neutral. As far as shutting the engine on and off, I have never heard a more ridiculous statement. You are gonna wear the starter out and burn more fuel turning it on and off inbetween. At idle these trucks dont use a ton of fuel.
Besides the starter wear, and fuel usage the possibly of the steering lock while flying down the freeway is just too frightening...not to mention no power brakes or steering. Not that we need power on a tiny little CTD truck though.:lol3:
 

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I can't really steer mine to well without power...

But those Insights have electric power steering (and weigh nothing), and they might have electric brakes too? I imagine they would.
 

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Starting and stopping an engine is hard on it. Sometimes engine shock cooling can happen or heat soaking when a hot engine is just shut off without a cool-down period. I would not want to turn off a hard working engine (especially a CTD) without a turbo cool down. Oil pressure would be a concern as well. Starting an engine and the few moments before Oil pressure comes back up is some of the hardest running time on an engine.

Ok--lots of concerns but not a lot of facts. I fly small planes and air cooled engines suffer from many of these issues.
 

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Doesn't the engine need to be running on a auto to "coast"? I know you can't tow an auto flat in neutral unless you have a transfer case to kick in neutral.

With the 5 speed, I kick it in neutral and cost every chance I can in traffic. I wouldn't think about shutting the engine off though.
 

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some of that is downright dangerous!!! Some of it is comon sense. I coast all the time, but I would never shut off the motor. Does't the insight automatically shut the motor down and start it up as part of the hybrid stuff??
I used to get close to 100 MPG on my old 91 CBR 600 when drafting behind semis going from LA to San Diego but it is scarry as heck! So much wind buffetting

Chris
 

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Discussion Starter #13
I have been driving down hill every where i go. it helps alot
Good gig if you can get it. :lol3: Do you mean you have been coasting downhill?

I would never turn the key off with the vehicle moving...just asking for steering lock or insufficient steering or brakes.

BUT. I do pop it into N. I don't care if it is illegal (how would they catch you?). I don't accept that it is dangerous. I could be convinced that it is not good for the tranny, or perhaps the engine.

I also used to fly light airplanes and also did some skydiving and hung out at the drop zones. Skydiving planes used to have a terrible reputation for cracked cyclinders because they climb fully loaded at full power up to altitude, dump their load, shut off the power (and sometimes even the ignition) and race the falling humans to the ground. The shock cooling was supposed to be bad. But more recently (and they still ain't modern engines) this has been shown not to be as much a problem as believed. Was it rumor? Is it more modern lubricants? Or is it still a problem? The current belief is that it ain't as bad. But that isn't a CTD with a 6 speed auto tranny in there being turned over by the force of 7000# rolling down the highway so the thinking may not carry over.

I would be interested in hearing other peoples' thoughts on this.

BTW. This has turned into quite a thread from what started as a mildly interesting article about extremists saving gas.
 

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Discussion Starter #16
Why? Does it burn less fuel in N than just coasting?

I suppose that is a good question. Not enough experience with the truck. And the overhead isn't going to help me figure that out. Haven't had a lot of automatics. My minivan (Toyota) I can be coasting downhill showing about 60-70mpg and drop it into N and it goes to 99mpg (max value). Also, the rpm drops to the idle value (800rpm on the minivan), whereas if I am coasting downhill in D then it will be 2000rpm or more. Now is it getting any fuel while the engine is being spun by the wheels? I dunno.

Smarter people, what do you think?
 

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A gas engine is thottled by the amount of air you put in it...a diesel by the amount of fuel...so wouldn't it stand to reason that a diesel at idle would be using much less fuel? I was always under the impression that a diesel at idle used very little fuel.
 

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If you're in neutral, you're loosing less energy due to parasitic drag. Not a factor if you're going to stop anyways, but if you're going to accelerate again at the bottom of the hill you'll save some gas. Like, three or four drops...

Turning the engine off on these hybrids isn't dangerous because the hybrids all got electric assist on steering and brakes. That is one of the major design features on a vehicle designed to operate much of the time without the engine running.

Now somebody explain to me how electric brake assist works so that I know I'm right?
 

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I would never dream of coasting in neutral in my pickup. For one, the payments are enough then to go and burn up the transmission and the fluid due to lack of lube circulation and the bearing wear you're going to cause and everything that's not working when you have that sucker in neutral. Think about that for a minute, would it be worth it to save $500 in fuel a year and then have to replace a $2500-$3000 trani? Seriously, don't trip over a dollar to catch that rolling nickel. You would be better off going out and buying a used 4-cyl or motorcycle and parking the truck.

Sorry guys...sometimes it seems to me that the long term effects are being blindsided by the short term results. Now...who wants a cigarette?
 

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Like stated...putting an auto in neutral and kicking it back into drive is no biggie but you prolly aren't going to see much from it with these...a gasser is a different story.

As far as shutting the engine on and off, I have never heard a more ridiculous statement.
NO S**T!! :thud:
 
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