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For an automatic, is it bad to coast down a hill (for short or long periods) in neutral and then just pop it back into drive afterwards? And what about "shifting" your automatic from say Low to 2nd or 3rd and then into overdrive? I have always wondered if this is bad or good, so anyone who knows anything, please let me know!
 

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I would not coast in neutral,just not worth it.
If you shift 1st 2nd 3rd all the time I would be afraid of shifter wearing out because they are not really made for that but it will be ok to do it sometimes.
 

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I've coasted in neutral to listen to various parts after I have lubed them. The risk, though, is you slip it into reverse while moving forwards, which is what I did.

If you do this, the engine immediately cuts out and won't start until you stop, put it in Park and try again.

So don't do it.
 

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I never heard of anything bad happening but just afraid 1 time something messes up and the $$$ it would cost.
 

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The lore for automatic trannys has always been that you absolutely do NOT want to coast in neutral for any real distance or at speed. Apart from the obvious safety issues, an auto tranny is designed for coasting while in gear. There are components in it that require constant lubrication. Apparently putting it in neutral prevents that to some degree, or so the legends tell.

It is fine to shift from L to 2nd to D to overdrive when the moment spurs you, and back down again as needed for engine breaking. You do NOT want to shift from N to D at every stop light though. The auto tranny is designed to remain in D when stopping or waiting at lights. Shifting between N and D wears it unnecessarily.
 

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JonRav4 said:
You do NOT want to shift from N to D at every stop light though. The auto tranny is designed to remain in D when stopping or waiting at lights. Shifting between N and D wears it unnecessarily.
Hi Guys, new member here!

I was just reading this post and the interesting comment by JonRav4 that automatics are designed to remain in D when stopped. This is my first automatic (and only my second car) but Im sure I read in one of the manuals that came with the car that stopping for a reasonable amount of time (at lights for example) and holding the break while in D can cause the transmission to overheat. Ive therefore been stopping > selecting neutral then parkbreak at every stop while I wait. Is this correct or am I better off staying in D? Sorry if this is a bit of a daft question.

Cheers,
Mark
 

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I seriously doubt there is a manual that says to take an auto tranny out of D at every stop. If you have to wait for a long time, like for a train or something, then yes, it makes sense to take it out of D. But not for your average light. Stay in D. Other opinions?
 

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JonRav4 said:
I seriously doubt there is a manual that says to take an auto tranny out of D at every stop. If you have to wait for a long time, like for a train or something, then yes, it makes sense to take it out of D. But not for your average light. Stay in D. Other opinions?
You're right, there's no need to take it out of D at every stop, but doing so will not cause any harm. Just about as much as not doing so. There is no more wear induced by switching from N to D than there is when the gearbox shifts on it's own.

If anything, leaving it in D when stopped will increase the oil temperature in the torque converter due to friction, but only slightly, and auto transmissions are designed to handle this anyway. While the engine is running transmission fluid is continuously being pumped in and out of the torque converter and through a cooling unit (usually a copper or aluminium pipe) to cool the fluid. When the car is stationary there is no airflow to cool the fluid but this usually isn't necessary due to the fact that less heat is being produced. Knocking it in to neutral disengages the torque converter completely, eliminating friction and hence stops the creation of heat almost entirely.

If your gearbox is overheating, the quickest way to cool it down is to pop it into neutral while the car is still moving. I always do this in my other car (Toyota Supra) when I hit the end of the drag strip because my torque converter is producing quite a bit of heat under full load.

At the end of the day though, do it, don't do it, it doesn't really matter. But like lan g said, just don't pop it into reverse, although most auto transmission levers will have a mechanical lockout to prevent this (i dunno about the RAV though).
 

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The reason I was coasting in neutral was this stupid forum's fault. I had just changed out my rear diff oil and the front transfer case oil as decribed on here.

It was running real smooth. And to hear it I wanted to coast with no engine noise.

But when reengaging the gear box I put it into R instead of D by mistake.

The engine just cut out and the Rav kept rolling foward. I think, but can't remember, it threw a CEL, perhaps flashing (since I did not have to reset it) as well.

It was quite clever really since the engine would not drive the Rav in reverse while it was going forward. It cut out immediately. No jolt or anything. It was like the Rav just said...."Nope".

What was clear is that I had to stop, and put it in Park before it would start again.

It would not start just by putting it straight back in Drive, which got me briefly worried that I had killed something.

I don't recommend anyone try it though.

But if my brakes ever fail, she's going straight into Park while in motion. I'll let you know how that one works out if it ever happens.
 

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ian g said:
It would not start just by putting it straight back in Drive, which got me briefly worried that I had killed something.
Cars with auto trannys invariably will not start in D. That's a safety feature.
 

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JonRav4 said:
ian g said:
It would not start just by putting it straight back in Drive, which got me briefly worried that I had killed something.
Cars with auto trannys invariably will not start in D. That's a safety feature.
Correct. Some will even REQUIRE that you have your foot on the brake as well. Others don't.

This is why I drive manual. My driveway is on a bit of a hill so I usually pull off the park break and roll down the hill before I even start the car just to get a head start. Try that in an auto.
 

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I've coasted in neutral to listen to various parts after I have lubed them. The risk, though, is you slip it into reverse while moving forwards, which is what I did.

If you do this, the engine immediately cuts out and won't start until you stop, put it in Park and try again.

So don't do it.
I've accidentally shifed by Gen 4 from N to R a number of times (not sayin how many). It seems to automatically recognize my error and seemingly stays in N. And the car just keeps on going. No need to stop,restart or anything like that.

Now when I accidentally shifted my mother's '67 Toyota Corona from drive to neutral on a freeway offramp about 40 years ago, it was another story. I think the car want a little air-born for a couple of seconds till I managed to get it back into drive.
 

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The lore for automatic trannys has always been that you absolutely do NOT want to coast in neutral for any real distance or at speed. Apart from the obvious safety issues, an auto tranny is designed for coasting while in gear. There are components in it that require constant lubrication. Apparently putting it in neutral prevents that to some degree, or so the legends tell.

It is fine to shift from L to 2nd to D to overdrive when the moment spurs you, and back down again as needed for engine breaking. You do NOT want to shift from N to D at every stop light though. The auto tranny is designed to remain in D when stopping or waiting at lights. Shifting between N and D wears it unnecessarily.
I think your quoted need to ramain in gear to benefit the auto trans is unvalid. I can't think o fany reason an idling car in neutral would suffer from not being in gear. If I'm wrong I'd like to know why specifically.
 

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Hi Guys, new member here!

I was just reading this post and the interesting comment by JonRav4 that automatics are designed to remain in D when stopped. This is my first automatic (and only my second car) but Im sure I read in one of the manuals that came with the car that stopping for a reasonable amount of time (at lights for example) and holding the break while in D can cause the transmission to overheat. Ive therefore been stopping > selecting neutral then parkbreak at every stop while I wait. Is this correct or am I better off staying in D? Sorry if this is a bit of a daft question.

Cheers,
Mark
I agree but don understand why you could apply the parking brake. I just shift to N and use the foor brake after coasting as far as I can without slowing so much as to obstruct traffic.
 

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For an automatic, is it bad to coast down a hill (for short or long periods) in neutral and then just pop it back into drive afterwards? And what about "shifting" your automatic from say Low to 2nd or 3rd and then into overdrive? I have always wondered if this is bad or good, so anyone who knows anything, please let me know!
Scotty Kilmer says that if you're at a really long stop, it's best to put the car into park to save the auto trans from overheating:

 
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