Can driving in neutral damage transmission?

[Atheria]

I just talked to a mechanic at my local Toyota/Scion dealership and he promised me that coasting in neutral with my car turned on would not hurt my automatic transmission. He said the only possible issue is that I would be putting the car in drive much more often (obviously) than a "normal driver". As long as I go back into drive smoothly and don't clunk the transmission, and as long as I change my transmission fluid as needed, I should be okay. There have been some times lately when it has just BUGGED me that I couldn't throw it into neutral.....great hills where I probably could have gone for miles without ever hitting the gas. :-)

[Gealii]

Make sure to use a scangauge/ Ultragauge to see if neutral or drive is better. I'm only saying this because on some gm cars the transmission shifts into neutral by itself although it keeps the rpms up and slowly decreases with speed, but according to the gauge I'm getting the the same instant mileage no matter what gear I'm in. Along with the actual can neutral damage your transmission just look it up in your owners manual how it should be towed, I know with jeeps for certain that the auto trannys need to be towed on a flatbed or they will burn up so neutral would hurt

[Atheria]

I need to Google what a scanguage or ultragauge is. :-) Well, my car is not supposed to be flat towed BUT the reason for that is having the engine turned off means no transmission fluid is being sent through the tranny. I coast with my car turned on. Although I seem to get the same 99.9 mpg if I'm neutral and coasting or in drive and coasting, the issue is that when I'm in drive, the car is "held back" by the gear it's in and coasts MUCH less distance.

[UltArc]

Originally Posted by Gealii

Make sure to use a scangauge/ Ultragauge to see if neutral or drive is better. I'm only saying this because on some gm cars the transmission shifts into neutral by itself although it keeps the rpms up and slowly decreases with speed, but according to the gauge I'm getting the the same instant mileage no matter what gear I'm in. Along with the actual can neutral damage your transmission just look it up in your owners manual how it should be towed, I know with jeeps for certain that the auto trannys need to be towed on a flatbed or they will burn up so neutral would hurt

Agree so much.

Originally Posted by Atheria

I need to Google what a scanguage or ultragauge is. :-) Well, my car is not supposed to be flat towed BUT the reason for that is having the engine turned off means no transmission fluid is being sent through the tranny. I coast with my car turned on. Although I seem to get the same 99.9 mpg if I'm neutral and coasting or in drive and coasting, the issue is that when I'm in drive, the car is "held back" by the gear it's in and coasts MUCH less distance.

I don't know about this situation, but like Gealli brought up, some cars are NOT more efficient in neutral. My wifes Escape in neutral picks up the rpms, while in drive it will be lower. True, there is drag from the transmission if the speed is greater than the engine speed by tranny, but if you are using MORE fuel to coast than less, it may not be worth while. The easist way is as suggested. That is what made me stop using neutral in her truck, is the increase in fuel usage while coasting.

[Gealii]

Originally Posted by Atheria

I need to Google what a scanguage or ultragauge is. :-) Well, my car is not supposed to be flat towed BUT the reason for that is having the engine turned off means no transmission fluid is being sent through the tranny. I coast with my car turned on. Although I seem to get the same 99.9 mpg if I'm neutral and coasting or in drive and coasting, the issue is that when I'm in drive, the car is "held back" by the gear it's in and coasts MUCH less distance.

As new as your car is it would be worth looking to see if you have dfco ( deceleration fuel cut off) which is basically an engine kill switch without turning everything off as long as you remain in gear. It cuts the fuel injectors while in gear. the reason it is showing 99.9 is because there is a limit to some gauges. the Ultragauge goes to 999.9 when coasting with engine off car on while I've heard the scangauge goes to 0

Also scangauge and ultragauge are fuel economy monitoring devices. they have the ability to show instant mpg, average mpg, engine load, intake temp, and many others by use of plugging into the obd2 port

[UltArc]

Originally Posted by Gealii

As new as your car is it would be worth looking to see if you have dfco ( deceleration fuel cut off) which is basically an engine kill switch without turning everything off as long as you remain in gear. It cuts the fuel injectors while in gear. the reason it is showing 99.9 is because there is a limit to some gauges. the Ultragauge goes to 999.9 when coasting with engine off car on while I've heard the scangauge goes to 0

Also scangauge and ultragauge are fuel economy monitoring devices. they have the ability to show instant mpg, average mpg, engine load, intake temp, and many others by use of plugging into the obd2 port

Scanguage ii goes to 9999.9, I believe. I think the highest I have seen under 9999 is 214 ish. Coasting, that is.

I have mine with red backlighting, in the format
MPH RPMS
MPG INSTANT AVG MPG

The Mustang speedos suck. It'sractically impossible to see the exact speed. I think so rim swapping won't show a difference, since Ford uses 17-20s, maybe higher.

[Gealii]

Originally Posted by UltArc

I have mine with red backlighting, in the format
MPH RPMS
MPG INSTANT AVG MPG

I have an ultragauge but my setup is

rpm Instant mpg
Avg mpg intake temp F
engine load % engine temp F

[Atheria]

Well, my RPMs do go lower when I'm in neutral. And, the issue is I cannot coast very far at all when in gear. I can go for a mile in neutral and not lose speed. :-)

[Gealii]

Originally Posted by Atheria

Well, my RPMs do go lower when I'm in neutral. And, the issue is I cannot coast very far at all when in gear. I can go for a mile in neutral and not lose speed. :-)

Its different for everybody u just gotta find wat works for wat vehicle

[Mustang Dave]

I use cruise control extensively, and get about the same MPG as coasting down every grade possible because my 4 liter V-6 consumes about .35 GPH while idling. Coasting down a grade in neutral (illegal in Arizona (ARS 28-895)) @ 60 MPG, I can get about 180 MPG. (Legal speed limit is 50 MPH). Going down that same grade @ 50 MPH with cruise control engaged and in DFCO, my ScanGauge shows 9999 MPG. UltraGauge shows 999.9 MPG. As they say, YOUR mileage may vary; one size doesn't fit all. (and I apologize for my earlier cynical remarks about psychics.)