stick22

so at risk of being torn apart here on the forum, i am going to ask a question about my driving technique.

i constantly put the car in neutral when coasting to a red light, waiting at a red light or longer stretches down hill. so... is this wrecking my transmission?

dengman

as long as your not throwing it in to drive at a high rpm or speed it should be fine.

Worst that could probably happen is the torque converter needs replace... Torque converter is like a clutch. Manual trans clutch is replaced when they are warn.

1111GS

Yeah I find myself doing similar thing (not just the GS), at the lights or ATM when I'm completely stopped. I know nothing about the transmission but I wouldn't want to do this and switch back to D while the vehicle is running though.
One thing I noticed the other day on the GS while at the ATM (it was so quiet and the window down), as I switched to N, the engine sounded a lot louder. I looked at the RPM and saw it went up a good 500 or so. I switched back to D, RPM went down, switched to N, it went up. I find this very usual. I expected RPM to go down as the vehicle went into idle but it went the other way. From that incident I stop switching to N on the GS. Maybe a transmission guru here can shed some light.

Pechanga20

Why the **** would you switch into neutral all the time? That's the torque converters job.

Chris8152

I personally don’t think that automatic cars are designed to go along in natural, and would think your doing more harm than good.
My GS has a “ HOLD “ button that when pressed will automatically hold the car when I have stopped, I can then take my foot of the brake while still being in “ drive “ and the car will not move, I am sure Lexus would not introduced this feature if they felt it would do harm to the transmission.

stick22

it was a carry over from the old days of driving stick... well i guess i have a new year's resolution now

Outrage

I tried to remain in a gear while slowing down when I drove a manual.

Outrage

Shifting the transmission in to neutral while decelerating will likely cause greater fuel consumption. When the transmission remains in drive there is a connection between the wheels, which remain rotating, and the engine which continues to operate. The vehicle will decelerate due to the vacuum created by the continued piston movement within the engine. Typically, the fuel to the cylinders will be restricted (cut off), as the engine can remain in motion due to the vehicle's inertia, which keeps the wheels in rotation.

Unlike a conventional manual transmission, which uses a clutch plate to couple and decouple the engine from the transmission, a conventional automatic transmission uses a torque converter to perform the task in a similar fashion using fluid coupling. The torque converter can be considered in a "slipping" state in most circumstances, so power distribution between the engine and the wheels is not 100% (unless it is "locked up"). This diminishes some of the engine braking advantages which is why you can rely upon that technique to a lesser degree when operating an automatic transmission-equipped vehicle. With this in mind, you'll see less of a fuel consumption difference with an automatic transmission versus a manual transmission.

None-the-less, there are a few additional advantages to keeping the vehicle in drive. You have additional mobility options when the vehicle is in drive. If you need to accelerate to avoid or a collision or maintain control of the vehicle you have those choices. From a transmission wear perspective, you are disengaging and engaging the gears each time you are shifting between neutral and drive. The various components involved in this process will encounter additional stress that they would otherwise avoid.

sarmyth

If it went up 500RPM most likely your car was cold and the engine was still trying to fire off the cats.

In my GS i've been shifting into neutral at stoplights as well... never did this in any other automatic I owned... For me I think it's because the car is putting so much force into trying to go forward when stopped in drive... most automatics aren't so forceful.

When you shift out of drive you'll see the RPM pop up as the load is released from the engine and then settle.

I doubt this will cause any real damage to the tranny so long as you're not dropping it from neutral to drive at high RPM (driveline shock is what happens when you do that) otherwise they'd be a warning in the owners manual about it right =P

When I was in Taiwan, shifting into neutral when stopped was common practice there... shocked me when I first saw it but it makes sense. Helps you save maybe a dime's worth of fuel over the course of a year =)

GiantsFan

iTrader: (9)

^the car idles LOWER when in gear ... at least this is true for every car I have driven.

Joeb427

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