is it bad to engine break ?

[alfa147x]

Some times SOME TIMES when i am driving my parents RDX when I come up to a red traffic light ill shift down.

That is engine braking right...?
well the question is this bad for the car?

Compression of gas and vapor requires energy as described by theories in physical chemistry and thermodynamics. Compression in an engine is driven by the forward momentum of the vehicle as well as the angular momentum of the flywheel. When a driver downshifts to spin the engine at high angular velocity (or RPM) without pressing on the [accelerator pedal], the engine converts energy from the vehicle's speed, which is kinetic energy, into a temperature increase in the fuel-air mixture. These hot gases are exhausted from the vehicle and heat is transferred from engine components to the air.

Jsk the RDX has a manual mode when you use the shifters located on the steering wheel

 

[TerryMathews]

Here's a better question for you:
Assuming no one can tell you with 100% certainity whether engine braking is damaging that car or not would you rather ruin...

A) Engine and/or transmission at a cost of between $2000 and $4000

B) Brake pads, under $100 at Midas

 

[alfa147x]

Originally posted by: TerryMathews
Here's a better question for you:
Assuming no one can tell you with 100% certainity whether engine braking is damaging that car or not would you rather ruin...

A) Engine and/or transmission at a cost of between $2000 and $4000

B) Brake pads, under $100 at Midas

True i shouldnt take the risk...

plus itll be like 30$ since i do the brakes my self

edit:

Damn its more then 30$ since its our first car with 4 wheel disk brakes

 

[Zenmervolt]

There is absolutely, 100% ZERO damage done by engine braking. Zip. Zilch. Nada. Unless you screw up and blow the shift, there's no extra damage from engine braking.

Now, if you are manually downshifting an automatic, you will cause a minuscule amount of wear on the bands in the transmission and maybe reduce the transmission life from around 200,000 miles to only around 180,000 miles. In other words, whoop-de-farking-do.

ZV

 

[ElFenix]

engine breaking is bad.

 

[Rike]

For ordinary driving, an engine and transmission is for going while brakes are for slowing down. At least that's what the guys on Car Talk say. It's makes sense to me.

 

[zerocool84]

Originally posted by: Rike
For ordinary driving, an engine and transmission is for going while brakes are for slowing down.

 

[natto fire]

Originally posted by: alfa147x
... when i am driving my parents RDX when I come up to a red traffic light ill shift down.

That is engine breaking right...?
well the question is this bad for the car?

Uh, the transmission automatically shifts down to first gear for you. That is why it is called an automatic.

Engine braking (engine breaking usually involves a sledgehammer) is holding the brake and flooring the gas to hit the torque converters stall speed.

If you are talking about shifting the gear lever to "L" or 1 at a stop light, you are not engine braking, in fact you are doing nothing that the transmission is already doing by itself...

 

[mwmorph]

Originally posted by: Captain Howdy

Originally posted by: alfa147x
... when i am driving my parents RDX when I come up to a red traffic light ill shift down.

That is engine breaking right...?
well the question is this bad for the car?

Uh, the transmission automatically shifts down to first gear for you. That is why it is called an automatic.

Engine braking (engine breaking usually involves a sledgehammer) is holding the brake and flooring the gas to hit the torque converters stall speed.

If you are talking about shifting the gear lever to "L" or 1 at a stop light, you are not engine braking, in fact you are doing nothing that the transmission is already doing by itself...

Engine braking is when you use the internal resistance of the engine, combined with gearing to slow down(higher gear + compressing air = friction to slow down)

Brake torquing or power braking is when on an automatic transmission car, you put one foot on the brakes and one foot on the gas to bring the engine up to the torque converter stall speed for a better launch.

To answer your question, yes you are wearing parts with every shift on an automatic transmission, but the parts you are wearing, clutch packs, bands, servos, hydraulic pumps, various springs in the valve body, etc, should outlast however long you keep the car regardless of the extra shifts.

 

[fbrdphreak]

Originally posted by: Zenmervolt
There is absolutely, 100% ZERO damage done by engine braking. Zip. Zilch. Nada. Unless you screw up and blow the shift, there's no extra damage from engine braking.

Now, if you are manually downshifting an automatic, you will cause a minuscule amount of wear on the bands in the transmission and maybe reduce the transmission life from around 200,000 miles to only around 180,000 miles. In other words, whoop-de-farking-do.

ZV

ZV speaks the truth.

But don't downshift an auto, unless there's a needed situation like hilly driving etc.

 

[Greg04]

Originally posted by: ElFenix
engine breaking is bad.

Says a crab who has no stake in the argument.

 

[Pacfanweb]

Originally posted by: Zenmervolt
There is absolutely, 100% ZERO damage done by engine braking. Zip. Zilch. Nada. Unless you screw up and blow the shift, there's no extra damage from engine braking.

Now, if you are manually downshifting an automatic, you will cause a minuscule amount of wear on the bands in the transmission and maybe reduce the transmission life from around 200,000 miles to only around 180,000 miles. In other words, whoop-de-farking-do.

ZV

/thread

And Merry Christmas

 

[bruceb]

An automatic will not downshift when the brakes are being applied, such as on a steep downgrade.
If you do downshift the automatic yourself, just watch the engine rpm .. try to keep it below 3000 rpm
to minimize excess wear on the tranny or engine ... And yes, properly done, engine braking is a good
practice. Big rigs use it and exhaust braking all the time to slow down. If they did not, the brakes would
not last very long and it would take much longer distance to stop. I had an 1985 RX-7 with 5 speed manual
and the first set of brakes went to 80K miles. OE clutch was still in it and ok when it was stolen about 130K miles.

 

[alfa147x]

Well When I Do Down Shift My Foot Is Off Of the Accelerator

 

[theeedude]

Originally posted by: alfa147x
Well When I Do Down Shift My Foot Is Off Of the Accelerator

Some cars automatically blip throttle for auto tranny downshift rev match. If yours doesn't, you should do it yourself.

 

[Zenmervolt]

Originally posted by: Captain Howdy
Engine braking (engine breaking usually involves a sledgehammer) is holding the brake and flooring the gas to hit the torque converters stall speed.

No. That's power braking.

Engine braking is using the engine's compression to slow the car down.

ZV

 

[angry hampster]

Originally posted by: alfa147x
Well When I Do Down Shift My Foot Is Off Of the Accelerator

I Feel Like I'm Reading An Ebay Page.

 

[theeedude]

Originally posted by: Zenmervolt

Originally posted by: Captain Howdy
Engine braking (engine breaking usually involves a sledgehammer) is holding the brake and flooring the gas to hit the torque converters stall speed.

No. That's power braking.

Engine braking is using the engine's compression to slow the car down.

ZV

Actually, that's brake torquing.

 

[fbrdphreak]

Originally posted by: senseamp

Originally posted by: alfa147x
Well When I Do Down Shift My Foot Is Off Of the Accelerator

Some cars automatically blip throttle for auto tranny downshift rev match. If yours doesn't, you should do it yourself.

First of all alfa, don't move the shifter in an automatic car unless the conditions call for a lower gear (hills, mountains, low traction, etc) or you're moving between P, D and R.

Second of all senseamp - I really hope you are kidding.

 

[Howard]

Originally posted by: Greg04

Originally posted by: ElFenix
engine breaking is bad.

Says a crab who has no stake in the argument.

You are a fool.

 

[natto fire]

Heh, perhaps too much eggnog last night?

Thanks all for the multiple corrections. On another note, what is some slang for engine braking for your region? Around where I grew up in Ohio, it was mostly called jake braking and the signs that prohibited it even had the words Jake Brake with the slash symbol.

I will refrain from giving advice under the influence from now on.
Merry Christmas.

 

[theeedude]

Originally posted by: fbrdphreak

Originally posted by: senseamp

Originally posted by: alfa147x
Well When I Do Down Shift My Foot Is Off Of the Accelerator

Some cars automatically blip throttle for auto tranny downshift rev match. If yours doesn't, you should do it yourself.

First of all alfa, don't move the shifter in an automatic car unless the conditions call for a lower gear (hills, mountains, low traction, etc) or you're moving between P, D and R.

Second of all senseamp - I really hope you are kidding.

I am assuming he is talking about manual shift mode on the RDX auto tranny. You know, the paddle shift thingys.
Why would I be kidding? You need to raise the revs to rev match on a down shift. I know Infiniti autos do it for you, they blip the throttle on downshift in the automatic, but not sure if Acura does it or not. If not, and you simply downshift without blipping throttle, you will feel a jerk back because the engine will be too slow for the shorter gear when the shift is completed.

 

[ElFenix]

Originally posted by: Captain Howdy
Heh, perhaps too much eggnog last night?

Thanks all for the multiple corrections. On another note, what is some slang for engine braking for your region? Around where I grew up in Ohio, it was mostly called jake braking and the signs that prohibited it even had the words Jake Brake with the slash symbol.

I will refrain from giving advice under the influence from now on.
Merry Christmas.

uh, no

http://en.wikipedia.org/wiki/Jake_brake

 

[jagec]

Originally posted by: TerryMathews
Here's a better question for you:
Assuming no one can tell you with 100% certainity whether engine braking is damaging that car or not would you rather ruin...

A) Engine and/or transmission at a cost of between $2000 and $4000

B) Brake pads, under $100 at Midas

You are not going to ruin your engine OR transmission by engine braking, unless you do it appallingly wrong. Invalid argument.

Engine [/i]breaking[/i] ruins the engine by definition.

Originally posted by: Captain Howdy
Heh, perhaps too much eggnog last night?

Thanks all for the multiple corrections. On another note, what is some slang for engine braking for your region? Around where I grew up in Ohio, it was mostly called jake braking and the signs that prohibited it even had the words Jake Brake with the slash symbol.

I will refrain from giving advice under the influence from now on.
Merry Christmas.

The "jake brake" on a semi truck is different from engine braking on a car.

 

[Throckmorton]

Unnecessary wear on the transmission.