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Lexus Owners Club > Lexus Models > Lexus GS 300 / Lexus GS 250 / Lexus GS 430 / Lexus 450h / Lexus GS 460 Club > Engine & Transmission
ajones1722
being new to auto boxes I was wondering are there any dangers to knocking into neutral and free-wheeling up to traffic lights etc?

I did this alot in my manual cars ao thought I try it me GS300 aover the weekend. All seemed OK. O know there's the argument about not being incontrol of the cars whilst its in neutral but was wondering if there are any detrimental effects on an auto box itself of such action?
Purvesh
I wouldn't have thought so.

I knock mine into neutral at lights, as I hate keeping my foot on the brake..
ColinBarber
don't do it, it is not good for the transmission.

Also doing it on a manual uses more fuel than if you leave it in gear.
ajones1722
[quote name='ColinBarber' date='Feb 28 2005, 03:10 PM']don't do it, it is not good for the transmission.

Also doing it on a manual uses more fuel than if you leave it in gear.
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wo! all those years I thought I was saving petrol and and engine wear :blush:
NickF
[quote name='ColinBarber' date='Feb 28 2005, 02:10 PM']don't do it, it is not good for the transmission.

[right][snapback]214648[/snapback][/right][/quote]

What does it do Colin? Is this why you're not supposed to tow an Auto for any distance?
ricky_is200
I believe your not supposed to switch the gearbox into or out of Drive whilst the car is moving.
chips229
Ive always been told never let a auto free wheel in neutral or to tow a auto.
peter026
[quote name='chips229' date='Feb 28 2005, 04:10 PM']Ive always been told never let a auto free wheel in neutral or to tow a auto.
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Correct :D
ColinBarber
[quote name='ajones1722' date='Feb 28 2005, 02:15 PM'][quote name='ColinBarber' date='Feb 28 2005, 03:10 PM']don't do it, it is not good for the transmission.

Also doing it on a manual uses more fuel than if you leave it in gear.
[right][snapback]214648[/snapback][/right][/quote]

wo! all those years I thought I was saving petrol and and engine wear :blush:
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[/quote]

When you come off the accelerator and the engine is revving over say 1300 rpm the ECU does a fuel cut - therefore zero fuel is being used. If you drop it out of gear the rpm goes to idle and fuel has to be used to keep the engine running.

This fuel cut is why you sometimes feel a jolt when coming on/off the accelerator.
ColinBarber
[quote name='NickF' date='Feb 28 2005, 03:10 PM'][quote name='ColinBarber' date='Feb 28 2005, 02:10 PM']don't do it, it is not good for the transmission.

[right][snapback]214648[/snapback][/right][/quote]

What does it do Colin? Is this why you're not supposed to tow an Auto for any distance?
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[/quote]

You shouldn't tow most autos because when the engine is off the fluid is not being pumped around the transmission.

Putting it into N is not a bad but fluid is not going around as fast as it perhaps should which could cause temperatures to rise.
Tron20
I always heard that towing an auto with the gearbox in neutral without the engine running, stopped the oil from being pumped between the transmission and an oil cooler, thus the oil would heat up in the gear box. For this reason when towing an automatic it should ideally have the back wheels off the ground, or it should be on a flatbed tow truck. Thats all i'm gonna ask for if my car ever breaks down, rather it was on the back of a flatbed. Although my Prelude actually caught the ground on teh bottom of the bumper coming off a flatbed...hmm


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