Neutral

[NTB]

I live in the Texas hill country, so have lots of opportunity to coast. On the last leg of my trip to the casa, I have two miles of slight incline so coast home in D, and the battery always gets home in the green. That said, can I use N at other times. I have read that I shouldn't use N above 60 mph, but other than that, is there any problem/harm with using N? P&G is a pain, can't I just slip it in to N?

[NoMoShocks]

<div class='quotetop'>QUOTE(NTB @ Jul 11 2007, 07:28 PM) [snapback]477272[/snapback]</div>

I live in the Texas hill country, so have lots of opportunity to coast. On the last leg of my trip to the casa, I have two miles of slight incline so coast home in D, and the battery always gets home in the green. That said, can I use N at other times. I have read that I shouldn't use N above 60 mph, but other than that, is there any problem/harm with using N? P&G is a pain, can't I just slip it in to N?
[/b]

I don't know all the technical specifics, but my gut feeling is to advise you against it. In general, this is not a good idea on any car with automatic transmission. Unless the transmission has a rear oil pump, it is starved of lubrication while coasting in Neutral.

I am not sure if that is the case with Prius, but since they warn not to tow it with all four wheels on the ground, it seem logical to realize that coasting in neural is pretty much the same thing.

The car is designed to get the best economy for the typical driver while coasting in Drive.

You should avoid using B (engine braking) on dowhill too, because that defeats regenerative braking. Use B only for extremely steep downhill where friction brakes come into play to the point you think they could onerheat. I haven't found any hill yet where I had to worry about that.

[Godiva]

Nope.

You need to glide.

Take your foot off of the gas and wait for the MFD to show green arrows. Then lightly touch the gas until it disengages the regen. You'll either see the arrows disappear, or be replaced with orange. Either way, your display will go 99.9 mpg. That's what you want.

No need to play with the stick. Drive will do you just fine.

[alexstarfire]

The thing is it's not always easy to do that, especially when your car is warming up. Sometimes it may take a while to get into that "glide" mode so by the time you do you already need to accelerate.

[Godiva]

<div class='quotetop'>QUOTE(Alexstarfire @ Jul 12 2007, 12:04 AM) [snapback]477349[/snapback]</div>

The thing is it's not always easy to do that, especially when your car is warming up. Sometimes it may take a while to get into that "glide" mode so by the time you do you already need to accelerate.
[/b]

Then you let the car warm up.

And you accelerate when you need to.

You learn to drive the car in "Drive".

[bwilson4web]

<div class='quotetop'>QUOTE(NTB @ Jul 11 2007, 09:28 PM) [snapback]477272[/snapback]</div>

I live in the Texas hill country, so have lots of opportunity to coast. On the last leg of my trip to the casa, I have two miles of slight incline so coast home in D, and the battery always gets home in the green. That said, can I use N at other times. I have read that I shouldn't use N above 60 mph, but other than that, is there any problem/harm with using N? P&G is a pain, can't I just slip it in to N?
[/b]

First off, "N" does not risk the vehicle except in one case, coasting down a grade starting with the ICE off and rolling faster than 42 mph. In this unique situation, the ICE would normally be started and run but in "N", the ICE won't run and MG1 will wind up spinning faster and faster. Toyota reports the NHW20, 2004-current, has a maximum MG1 rpm of 10,000 rpm. The NHW11 is reported to have a 6,500 rpm MG1 limit but we already know it can go to 8,500 rpm in "P" with the accelerator maxed.

If you are already above 42 mph, "N" is vehicle safe at any speed. If you stay below 42 mph, "N" is vehicle safe. It is only starting below 42 mph with the ICE off and rolling down a hill and exceeding 42 mph that you'll be violating existing control laws.

The transaxle oil pump is operated by the ICE.

Bob Wilson

[hobbit]

Just to play devil's advocate a little here, I've had my own NHW20
in "warp neutral" fairly often -- into the mid fifties, even, and
as a test I once had it up to about 68 on a big downhill with the
engine stone cold stopped and MG1 howlin' away at 10 grand or over.
Air resistance kept me from going any faster, as probably did the
windage around MG1 and MG2 themselves down there in the transaxle.
But mild episodes of warp-neutral to carry one through little dips
and valleys without spinning the extra metal of the engine is pretty
harmless.
.
_H*

[NoMoShocks]

<div class='quotetop'>QUOTE(hobbit @ Jul 12 2007, 12:05 AM) [snapback]477381[/snapback]</div>

Just to play devil's advocate a little here, I've had my own NHW20
in "warp neutral" fairly often -- into the mid fifties, even, and
as a test I once had it up to about 68 on a big downhill with the
engine stone cold stopped and MG1 howlin' away at 10 grand or over.
Air resistance kept me from going any faster, as probably did the
windage around MG1 and MG2 themselves down there in the transaxle.
But mild episodes of warp-neutral to carry one through little dips
and valleys without spinning the extra metal of the engine is pretty
harmless.
.
_H*
[/b]

How can you make this claim that it is harmless? Have you done a comparison at high mileage between two Prii, one run with multiple instances of warp neutral, and another high mileage control car that has not been abused that way? What if latent damage from the warp neutral doesn't take it's tole until 160,000 miles? Why risk it? What is the point?

If what you say is true, than why does Toyota recommend not towing the car on all four wheels? What is the difference? Oh, you should be able to tow in warp neutral, as long as it is only done ocasionally! Mostly up to 42, but sometimes it is OK to tow it at 50, and you can even go 68 if you must.

[gazz]

<div class='quotetop'>QUOTE(hobbit @ Jul 12 2007, 02:05 AM) [snapback]477381[/snapback]</div>

Just to play devil's advocate a little here, I've had my own NHW20
in "warp neutral" fairly often -- into the mid fifties, even, and
as a test I once had it up to about 68 on a big downhill with the
engine stone cold stopped and MG1 howlin' away at 10 grand or over.
Air resistance kept me from going any faster, as probably did the
windage around MG1 and MG2 themselves down there in the transaxle.
But mild episodes of warp-neutral to carry one through little dips
and valleys without spinning the extra metal of the engine is pretty
harmless.
.
_H*
[/b]

Yes I have some short distances, say 1/2 mile which I know I will have to stop or slow right down and it seems ashame to add that extra drag for just 10-20secs, I limit it to about 50mph for short periods.

[gazz]

<div class='quotetop'>QUOTE(hobbit @ Jul 12 2007, 02:05 AM) [snapback]477381[/snapback]</div>

Just to play devil's advocate a little here, I've had my own NHW20
in "warp neutral" fairly often -- into the mid fifties, even, and
as a test I once had it up to about 68 on a big downhill with the
engine stone cold stopped and MG1 howlin' away at 10 grand or over.
Air resistance kept me from going any faster, as probably did the
windage around MG1 and MG2 themselves down there in the transaxle.
But mild episodes of warp-neutral to carry one through little dips
and valleys without spinning the extra metal of the engine is pretty
harmless.
.
_H*
[/b]

Yes I have some short distances, say 1/2 mile which I know I will have to stop or slow right down and it seems ashame to add that extra drag for just 10-20secs, I limit it to about 50mph for short periods.