Will it cause harm to the car to shift it into N just before stopping at red lights, or when traveling down a hill etc?

 

If your trying to save gas that way. You don't save anything noticeable; and if you had to put it back into gear and end up screwing the transmission then you'll paying A LOT more than what you would be saving doing this (a couple cents a month). It's why the owner's manual tells you not to rev in P or N.

EDIT: after asking a car friend:

why not to put an automatic car in N going down a hill or at a light.

1. down shifting; or taking your car outta gear wears out your lower gears quicker.

2. when you are going downhill in a car that is an automatic then engine isn't really doing anything, unless your pumping the gas or break.

3. while your in neutral your engine is still running; so you are still using gas.

4. while your car is in neutral some cars lose the steering controls or power braking.

5. if an emergency arises (deer, we have lots of these in our hills. police, these too, haha) you might not remember to stick it back into drive, and you'll end up hitting the obstruction.

 

Leave it in gear, you actually use less fuel since the forward momentum is turning the engine and the injectors shut off. If you take it out of gear, the engine has to burn fuel to maintain idle.

 

Nothing here is the right answer...

1) Your gears do not wear out quicker...Gears only wear quicker when they are under load, even then it is hardly noticable.

2) The engine is still doing everything, except driving the transmission, which is obviously in neutral.

3) Yes...but any engine running uses gas.

4) No they dont...you still have vacuum for break booster, and your belt is still driving your power steering pump.

5) How does an engines transmission being in neutral automatically make you hit deer?!

The MAIN issue with putting your transmission in to neutral when you are driving is this...
**Your transmission oil pump is no longer in operation, it is also in neutral**
You will loose lubrication and cooling. Plain and simple. Sure you will save a few MILILITERS in gasonline, but who really cares about a few cents when you are talking about something that is worth THOUSANDS.

Any other 'theory' is useless...Just leave it in gear and enjoy the automatic transmission.

 

Mine is so noisy that I put in netrual when slowing down just to relive the drivetrain.

 

The rule I live by in this situation is:

Brake System < Transmission System

when it comes to cost of repair.

 

You got it...brakes are cheap (relatively).

 

You have an automatic trans.?

 

It even says in the manual to put it in neutral when stopped for long periods of time. So i doubt its bad at all to do if the manual says to do it. On the other hand its kind of gay to do anyways as the injectors shut off when you are off throttle. Thus not burning anymore fuel then you would be at idle.

 

The manual's right -- switch to neutral when you're stuck in a traffic jam. Otherwise, you really shouldn't have bought a Ralliart if fuel consumption is a major concern, so keep it out of neutral if you're the one who bought the car, unless you want to look like a complete idiot.

 

At longer lights or stopped for periods in traffic longer than expected ie construction zones I always put it in neutral or park. The SST gives the 'feeling' of an automatic with creeping along at stop lights ect. The SST is actually slipping the clutches to simulate this, so if you think it wont wear out the clutch faster the more you sit there with your foot on the break in gear then id be surprised. Only time will tell with the longer the SST is around and what long term issues come up!

 

Big difference in putting car in neutral coming to a stop sign/coasting down a hill and sitting still in traffic. Like the owners manual says if you are going to be sitting idle for any period of time you should place it in park or neutral. Nowhere is said manual does it state to slip it in neutral while coasting to a stop/downhill.

 

The main problem is when you move the gearbox into drive or gear. If the car is still moving you will cause damage. If the car is stationary then there is no problem.

 

you will not cause damage, ive done it several times at hwy speeds, no lurching(quite smooth actually) no grinding, no jerking no over reving. Just like a damn auto actually maybe even better.

 

This is true. ^^