[Gonzo]

What are your thoughts on this?

When setting in traffic (stop and go or sitting) I've been placing the CVT into Neutral. When traffic starts I pop it into D we my feet off the brake.

Anything wrong with this repeative process? Anything wrong with putting it into "gear" with my foot off the brake?

Should I just leave it in D the whole time?

 

[Kris]

Hi Gonzo,

an interesting question. I've been doing the same but much less often. Only when I get stuck in a traffic for longer periods.

I do not think it should hurt the CVT. The computer controls so much that even it you driving at 70 mph and put it in "L" nothing happens. The RPM just go up a little bit.

Anybody with experience on this one?

 

[NVMYGT]

Why do you place it in neutral? I've never done this with any car that I have owned that was an auto. Granted, the CVT is a slightly different beast, but I still don't see the reason.

 

[Tyler_Canada]

I’ve started doing this to keep the transmission fluid a little cooler. Doesn’t churn it in the torque converter when it’s in Neutral. Should improve the life of the fluid a bit. Of course you wear whatever mechanism is responsible for going in and out of “gear” by doing this. Always a trade-off. Like choosing between transmission (engine) braking or brake braking. Which one do you want to wear?

 

[Eric L.]

I doubt this would hurt the transmission much (shifting to neutral at a stoplight).

However consider this. Nissan probably did desert testing of the Murano under extreme heat, so the CVT cooling system is probably adequate. However, I doubt some test engineer shifted it from D to N and back again a thousand times to see if the shift mechanism would wear out.

Just something to think about. I admit that when I am stuck in traffic (or just the drive through) I put the car in neutral and put on the parking brake for the very same reason you do - to cool the transmission fluid.

Gonzo - you should always have your foot on the brake when shifting into a drive gear (R or D). Ok I admit I don't have a good reason why, but I've always done it and I would feel strange if I did not. I hope you are not sitting at the stoplight in neutral with your foot off the brake. What if you are rear ended, you'll slam into the car in front of you.

 

[jetnbye]

The odd time I find myself putting the CVT into neutral (old habit from driving standard) when approaching a red light from a distance.

This helps to break faster since there is no added drag to the brakes from the CVT & engine, and also prolongs brake pads.

And secondly the RPM's drop to idle therefore saving some gas I suppose

 

[Eric L.]

The odd time I find myself putting the CVT into neutral (old habit from driving standard) when approaching a red light from a distance.

This helps to break faster since there is no added drag to the brakes from the CVT & engine, and also prolongs brake pads.

And secondly the RPM's drop to idle therefore saving some gas I suppose

I think the savings in brake pad material and gas is offset in this case by the inability to accelerate if needed to maneuver around an obstacle. I remember hearing a caller on Cartalk ask Tom and Ray about this, "coasting in neutral" and they recommended against it, and I agree.

 

[Tyler_Canada]

I think the savings in brake pad material and gas is offset in this case by the inability to accelerate if needed to maneuver around an obstacle. I remember hearing a caller on Cartalk ask Tom and Ray about this, "coasting in neutral" and they recommended against it, and I agree.

This is true for using N when stopped too. It's especially dangerous for us, as the Murano waits a good while after going from N to D before allowing much power.

Also, it's a bit embarassing to accidentally rev in neutral when a light turns green because I forgot I put it there.

 

[Gonzo]

jetnbye,

Actually if you leave it in gear (with CVT or manual tranny) it WILL help you slow down and therefore less braking will be needed. You want the "added" drag to help slow down. I always leave it in gear when coming up to a red light... just let up on the gas and the car reduced in speed without using brakes. If you are in neutral the car will want to coast more.

Eric,

I know what you mean by putting your foot on the brake. But from N it is one click down. I'm looking behind me, since I'm stuck in traffic nobody behind me is moving. Also even with you foot on the brake (Depending on speed) if someone hits you you are gonnna move forward.

Just think about it... if everyone left there foot off the brake and someone hit someone from behind we would all just "pass the engergy" though and nobody will get damage. With your foot on the brake you absorb it and then something has got to give. Yea yea I like that... everyone take you foot off the brake! :4:

 

[Eric L.]

Hehe I am not sure if I buy the foot off brake absorbs energy argument. But I guess you can do whatever you want, if it works for you.

Another reason to leave your foot on the brake is so the car behind you doesn't think you are going already and run into you.

 

[MightyMo]

Wow, the number of myths stirred up in this thread are amazing, let me try to dispel a few here...

On *all* modern fuel injected vehicles, when you are coasting with your foot of the gas *and* in gear the ECU totally shuts off fuel delivery. This means not only are you getting extra engine breaking to slow the car down, but you're also saving gas. If you pop the car in neutral you loose both effects. Also, when at speed but with the engine at idle your accessories are possibly dangerously underpowered...you want that super heavy power steering problem on the Mo to bite you when you're doing 50MPH and need to dodge some idiot? Please people, just say no, leave it in gear.

Having your foot off the break when rear ended does allow some of the energy transmitted from the other car to go into accelerating your car instead of just caving in the rear bumper even more. However, this means you will probably get front end damage from hitting what ever is in front of you, you may easily loose control of the vehicle if you are hit hard enough, and think about getting punted over some pedestrians in the cross walk or out into an intersection and getting t-boned by cross traffic. Please people, again just say no, don't do it.

 

[Kris]

MightyMO,

I making a good point. You make me think..........I guess I will stop putting the CVT to N when on red lights (anyway, I do not do it often).

As to coasting - I would never do it! Neither with CVT, automatic nor manual for various reasons.

 

[hfelknor]

Lemmee tell you about the most ridiculous ride I ever took in an automobile.
A long time ago in a galaxie far, far away........
Well, it was 1964 in Montgomery Alabama.
And my ride was a 1957 Plymouth Golden Fury with a 1964 Hemi Racing engine crate motor w/no warranty.
Coming back from the local outlaw track, I was challenged by my buddy who had a Show and Go customized 56 Buick w/ a supercharged Buick 400 CI dragster engine.
We ran from about 75 up to about 145 and I had pulled ahead almost a car length.
I was in the oncoming lane to his left.
Way down the road I saw a farmer pull on the road and come toward me with a tractor.
So I let off the loud pedal and..........and the pedal came up, but the engine continued to rev!
My buddy kept a constant speed for some time and then realized I was in some sort of trouble and let me come over.
I blew by that Tractor at about 135 MPH. We never did go back to see if the Farmer was OK.
Now I was approaching a major intersection at about 125MPH.
the brakes were not slowing the cardown fast enough, because th engine was still pulling hard.

Well I panicked.
My hand was on the builtup Torqueflight tranny so..............
I pushed Neutral.
The engine momentarily saw 150,000 RPMs (Well it seemed like it!) so I quickly turned the engine off.........
You guys talk about Neutral............
You should try neutral through a redlight (with most of your friends at the drive in on the corner) at better than100 MPH.

The power steering is gone, the power brakes are gone and I am suspended in the air.
My feet are both on the brake, and my shoulders are against the seat back. My hiney is a good foot off the cushion as I pushed with everything I had on that brake pedal.

When the cop got there, about a half mile down the road, I had just lifted the hood and discovered that the linkage on the dual 4 barrels had come loose, and the "front" 4 barrel linkage had jammed down on the intake manifold sticking that Carb wide open.
My fault. We had just put the engine in that thing a few weeks before.

I guess I looked pretty pathetic, because once the cop saw what had happened he let me go.


So the next time you get the urge to Put it In Neutral, think of the Old Man (who was young then) going through a red light, with his
a$$ suspended in the air trying to stop a car doing 100 MPH without steering or brakes.
Little guy.
Big eyes.




BTW the engine survived that little debacle just fine.

Homer

 

[senza]

I often when stopped in traffic shift into N I think "just for something to do"...sounds like a bad habit...which foot does everyone use for the brake pedal? I always use left foot with right foot ready to "put the pedal to the metal"...another bad habit from my street racing days of my youth..

 

[Gonzo]

Nice info.... some great points. Thanks fellas.

 

[GMTURBO43]

I gotta call BS on the guy calling BS.

If the ECU were to completely shut off the fuel system - the car would stall. There will always be fuel pressure at the injector(s) as long as the car is running.

The amount of fuel you are going to save in either case is minor - it is when you floor it from the stop light that is going to use more fuel.

There are a few ways you can look at it. If you are concerned about the trans temp - install an aftermarket transcooler. Shifting from N to drive is going to cause a 'jolt' to the driveline components that are sitting there with no force being applied.

Look at it this way - what is better to sit at a light 'power braking' at 3K RPM or to put it in Neutral rev to 3K RPM and then drop it into Drive as the light changes. They each have their problems - although I'll take my chances by not doing a 3K RPM Neutral Drop.

Now, onto to another reason as to NOT go to N and not covering the brake. You have no brake lights. With as many absent minded drivers out there - I'm going to do everything I can to be seen.

 

[Kris]

Hfelknor

Great write up. It reminded me my first car with manual stick. It was winter, lots of snow (not in Atlanta course!). I was driving slowly and needed to cross railway track. Not a problem. Unfortunately my darling said “drive slowly!”, so I did. What I did not realize there were dip indentations in snow made by train wheels. Car simply got stuck as the distance between the indentations (12 inch deep) and car wheelbase was identical! So there I was literally spinning the wheels! In the middle of nowhere. Stuck on a railway truck.........Got out of car and said to my wife please try to drive and I will push. And push I did. What was weird I could hear the engine revving really high but there was still no car movement! So I walked around the car and saw NO WHEELS spinning! Hm, weird indeed. Then I realized – the tranny was in neutral!!!!


Since then we never had a car with the manual g/box..............

I know it is off-topic but hfelknor “inspired” me......

 

[MightyMo]

No, the engine does not stall when the ECU shuts off the fuel delivery, the engine is being driven by the drive wheels during decelertation and in gear.

Line H of Page #27 of the Engine Control section of the 2003 Murano service manual states:

"FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds."

You are right, the fuel pump still runs, as long as the ignition is on and the engine is turning (as by the Crank and Cam angle sensors) the fuel pump will continue to presurrise the fuel system, but that doesn't mean any fuel is actually being used by the injectors and ECU.

 

[Tyler_Canada]

No, the engine does not stall when the ECU shuts off the fuel delivery, the engine is being driven by the drive wheels during decelertation and in gear.

This is correct. The injectors are not "pulsed", and no fuel is entering the cylinders. Even if you "downshift" into Ds or L. So you use less fuel by coasting in gear than in neutral.

 

[GMTURBO43]

Interesting.

I'd be curious to see a scope on the injector signal during deceleration. Jaak - ya up for it?

There has to be something keeping it running. It isn't as though the engine is just spinning on its own.

I'm not doubting what you say - just questioning the manual