shifting from neutral to drive

[noogieman]

keeping foot on brake waiting long time for green light will wear you pads and rotors if stick is left in D

 

[MancMike]

How? They’re not spinning and wearing away material?

Are you suggesting if I put my car in D and wedge a stick against the brake pedal with clean wheels for a week, I’ll come back to a pile of brake dust and a pad shaped indent in the disk?

 

[noogieman]

car will pull forward in Drive when you are standing still, you apply footbrake to keep car stay in place.
there will be friction

I always put in N at redlight when it's the queue

 

[renault12ts]

car will pull forward in Drive when you are standing still, you apply footbrake to keep car stay in place.
there will be friction

I always put in N at redlight when it's the queue

If you come to a halt using your brakes (how else?) and do not move your foot off the brake then there is absolutely no more wear on your brake system no matter how long you are sitting there. Static friction in this case will cause no wear, but if you allow the car to creep then yes there will be (negligible) wear from kinetic friction.

 

[noogieman]

my car always pulls forward in D when in stationary.
I don't always put it in Neutrale only on long waits at red light with the foot on the brake.

 

[renault12ts]

my car always pulls forward in D when in stationary.
I don't always put it in Neutrale only on long waits at red light with the foot on the brake.

Yes it pulls, but if you do not allow it to actually move then there will be no wear. Think about it. It's the same as having your car parked on a steep slope...the tyres will not wear yet the static friction is much greater than when the car is parked on a level surface.

 

[noogieman]

Yes it pulls, but if you do not allow it to actually move then there will be no wear. Think about it. It's the same as having your car parked on a steep slope...the tyres will not wear yet the static friction is much greater than when the car is parked on a level surface.

I have highlighted your sentence.
this is what I ment with wear on pads and rotors if you leave the gear lever in D while waiting long time at the redlight, car pulls forward and you have to apply footbrake standing still.
metal on metal must cause friction and wear mostly to pads coz discs are solid steel and don't wear as fast as pads.
pad compound is softer than disc.

therefore I many times put the stick in Neutrale also holding foot on brake, no pull forward no wear on pads

it won't cause any damage to transmission when I stand still and shift lever to N

 

[renault12ts]

I have highlighted your sentence.
this is what I ment with wear on pads and rotors if you leave the gear lever in D while waiting long time at the redlight, car pulls forward and you have to apply footbrake standing still.
metal on metal must cause friction and wear mostly to pads coz discs are solid steel and don't wear as fast as pads.
pad compound is softer than disc.

therefore I many times put the stick in Neutrale also holding foot on brake, no pull forward no wear on pads

it won't cause any damage to transmission when I stand still and shift lever to N

But unless the car is actually moving there is no wear.

You apply the brakes to come to a stop and the parts are wearing, but when the car has fully stopped the wear also stops.

Am I misreading this?

 

[markmifsud]

The only thing I can think of is that if you keep your foot on the brake after heavy braking, it can sometimes bake the top layer of the pad to the disk.

 

[renault12ts]

Indeed.

 

[noogieman]

But unless the car is actually moving there is no wear.

You apply the brakes to come to a stop and the parts are wearing, but when the car has fully stopped the wear also stops.

Am I misreading this?

this is what I think tell me if I got it all wrong or not?

keeping the foot on brake while gear lever is in D, car pulls forward so you have to apply brakes to keep car to stand still, small wear and friction to pads must occur and possibly cooking the pads if discs are glowing hot?

keeping foot on brake while stick is in N, car doesn't pull forward, there is no force on brakes to keep car stay still because car isn't pulling forward.

it's a difference on up or downhill, there I would probably stay in D at redlight

 

[renault12ts]

Static friction causes no wear.

 

[brucemillar]

Guys please.....

If the car is stationary. Then there is no wear, no friction. no stress. Simple.

The pressure applied to the brake pedal - then to the discs and pads is simply that - pressure. Pressure does not cause wear on any component that is not moving. This is very, very basic physics. If you doubt this? then you really should not be on the road. Harsh but true. Do you check that your spare tyre is not needing replacing as it is also moving in the car as you drive along. So by your theory, it has done the same miles as the road wheels and must need replacing when they do ;^)

Just off to check that I have not bought any 'out of date' engine oil.

 

[MancMike]

It’s also static friction that holds your wheel to your disc and your disc to your hub.

The tention in the bolts maintains the level of friction way above any movement being possible.

 

[brucemillar]

As an experiment: Take a coin, any coin (it doesnt have to be your own coin, borrow a coin). Now sit the coin on a flat surface (lets say a desk top).

Now: Lightly press down on the coin with your thumb. Do not attempt to move the coin or, to move your thumb. Just apply a light downward pressure. Do this for maybe 40 seconds (about as long as you would sit stationary at traffic lights).

Now: Remove your thumb from the coin and inspect, first your thumb, then the coin, then finally the desk. Are any of them worn down or displaying signs of needing replacement? Is there any indication of a trench having been cut into your desk by the coin? Has the skin on your thumb been ground away exposing the naked bone beneath?

Nope... There is your answer.