rzee

if I rev up my 5AT at neutral, then drop it down to D or M? Is that going to do any good or is that going to kill my transmission?

moreace_RENAMED

very bad, just don't do it

Handruin

Try it and let us all know.

My guess is you will be calling a tow truck after a few of those.

TsXtian

you don't do that to your own car...... you do it to rental cars only

ebcheon

:shakehd:

moreace_RENAMED

Quality response by eb
def the best so far
simple and to the point

rzee

Thanks for all the responses. Care to explain?

DjElucid

I'm no mechanic but I'll try. In a AT, gears have to go in consecutive order, you can't specify what gear you want. If you shift it into neutral and then back into drive, your car will have to go from 1 to 2 to 3 to 4...very quickly depending on what speed you're going to acomodate your gear with your speed.

Handruin

Simply, the torque converter is not designed to handle that level of stress/pressure from the crankshaft if you rev the engine before placing it into gear.

Think of it like this. Imagine you are holding your legs of the ground and you start running in motion as fast as you can. Then you immediately drop to the ground...wouldn't that hurt like hell?

rzee

How do we know the torque converter can't handle it?

provench

You're right ... it can ... you first

What do I care anyway .... 6MT is the only way to go

Handruin

I don't know for 100% acuracy sake, but it's a safe bet that if you rev the engine and drop it into gear, you're going to damage something. If not the torque converter, perhaps the CV joints or something else in the drivetrain.

rzee

Maybe I should go test drive one. :P

kenbiddulph

Its very bad on the torque converter. Imagine what happens when you have sticky 17 inch wheels that DON'T spin from you doing that. All that energy has to go somewhere and it sure does ,all at the expense of your transmission. Honda transmissions aren't cheap so don't do it unless you have a manual (its not as dangerous but its not healthy either) or a lot of money to replace it.

moreace_RENAMED

if u don't wanna believe us and u r set on it, tehn just do it. We'll all have a good laugh later, at least we will

fdl

Ahh...the neutral drop. Not a good idea. Brake torquing might be a better idea for a hard launch.

Go to www.howstuffworks.com and read up on torque converters.

DjElucid

So on my MT, I can't rev it up and drop it into gear? I know I can.... but how unhealthy is it? I thought that was one of the best parts of a MT?

ClutchPerformer

It's fine......as long as the clutch pedal is pushed down when you're doing it.

And by the way, why would you want to drop your AT into gear at 5000RPM anyway? If you're trying to get a fast start, just load up the brakes and let it loose.

rzee

Well, I obviously won't try that on my own ride.

rzee

I am just used to doing that on MT and wondering if it can be done on an AT.

DEVO

You guys are all wrong. A torque converter will handle that with no problems... a manual on the other hand will not. You will burn the clutch if you keep doing that. Let me ask you this... why do drag racers use automatics? The reason is that a torque converter can handle higher stresses then a clutch.

rzee

Now thiiiiisssss is interesting...

fdl

I think both clutches or torque converters can be designed to handle higher stresses. Dont forget you can buy very hard clutches design for high torque launches/shifting. Same goes for torque converters I suppose. I still think 1 would rather put 1000 hard launches on a TSX clutch, than 1000 neutral drops on a TSX torque converter.

DEVO

Maybe you guys don't understand the differences between a clutch and a torque converter... a clutch (simple terms) has a clutch plate and a flywheel. When the 2 come into contact you will get movement. Now there is a lot of friction and wear that occurs when one plate is spinning much faster then the other. The only way to get both to spin at the same speed is when they come into contact.

So if you are revving your engine, the flywheel is spinning at a high speed, while your clutch plate isn't moving at all (assume at a stand still) when you engage the 2 plates there is lots of forces at work here and lots of wear. You are forcing the clutch plate to absorb the pressures and weight of the car against the flywheel which also puts stress on the engine. What tends to happen is that the clutch plate slips against the surface of the flywheel surface until fully engaged. This is also known as burning the clutch.

On a torque converters you have no burning of anything. You have 2 parts that move through hydraulic pressures. So one side has to spin up to the speed of the other. Therefore a lot more stress can be handled in such a setup. There are no contact plates. Anyway, I hope this simple explanation helps.


I doubt you can get a 1000 drops (rev 5K and drop clutch) out of a manual transmission. I doubt the same for an automatic, but I'm betting that you can get more drops out of a automatic then a manual.

brerpie

Kind of on topic:

It's ok to switch from Drive to Sportstronic back and forth at any time/speed without being at a complete stop right?

rzee

I am with you on this, in theory at least. However, since I don't know any drag racer, I can't confirm if this is the reality or not.

rzee

Yes. C'mon brerpie, this is so off topic, I thought we explained this before already.

ClutchPerformer

Don't drag racers use manuals? If you watch a drag event on TV, you can see them shifting. And why would they have shift lights, etc. if they had autos?

bbbuzzy

My two cents: You will wear out your torque converter prematurely. Sure it will handle a bunch of "neutral drops" but the energy has to go somewhere. Kids did this often back in high (20+ years now, yikes!) on Dodge Darts, etc and nasty noises were produced. It was fun for a while but soon enough someone would trash the car. Don't destroy your TSX, buy a rear wheel drive car, lock the brakes and spin the wheels prior to launch.

DEVO

nope... they use autos... what you are seeing is gear selections which is no different then sports selections mode in auto.

they have dedicated gears and the gears are designed to take a lot of stress... but they run a torque converter with manual selection of gears.

DEVO

i think everybody is an agreement that this shouldn't be done... i think the debate is which system can handle the stress better. I'm of the opinion that a torque converter will last longer under identical drops versus a clutch.

torque converter, the transfer of energy is indirect (through hydraulic fluid).... clutch, the transfer of energy is direct (friction on clutch plate).

civic4982

neutral bomb that baby!!! j/k, if you keep doing it, one of these days you'll see the transmission in the rearview mirror.

XPLORx4

I was under the [possibly incorrect] impression that the shift from Neutral to Drive on an automatic tranny was not so much a torque converter thing as much as a gear engagement thing.

The way I understand it, the TC is always connected to the flywheel, and in Neutral, the plantary AT gears of the transmission are not engaged with the TC. When you shift into gear, the planetary gears engage the rotating TC.

So, is the problem with revving it and shifting into gear more of an issue with wearing the gear teeth or transmission bands?

LeeLee

NO NO NO NO NO!!!!!

Neutral dropping is very bad for the automatic transmission and will destroy it far quicker than clutch dumping on a manual transmission. Here is why:

Even though it is an "automatic" transmission, it has little hydraulically actuated clutches that engage each gear. The bump you feel when your automatic transmission shifts from gear to gear is one clutch releasing and another clutch engaging.

These little clutches are small because they are not made to slip. Once they engage they lock in fully and it is the fluid-coupled torque converter that does all the slipping. The torque converter will withstand monumental amounts of torque before failing because that's what it is designed to do.

Normally, when you first put your transmission from N into D, the first gear clutch engages. Since the engine is ideling, the clutch slips very little as the torque converter input shaft comes up to speed with the engine. You feel this as that slight bump you get going into D.

When you neutral drop, the engine is reving at a high RPM, carrying considerable amount of inertia, which is directly transferred to the first gear clutch. As a result the first gear clutch slips considerably. Since automatic transmission clutches are small in diameter and are not made to withstand significant amounts of slipping, it doesn't take long for the clutch to be destroyed.

Such a transient mechanical shock will also do wonders to your transmission gears. In the mean time, the torque converter couldn't care less. It's fluid coupled and is built to withstand huge amounts of torque.

On the otherhand, a manual transmission's clutch is HUGE in comparison and is made to withstand slipping. Therein lies the difference and the reason why a neutral dropping an automatic transmission will bring you a few grins plus a $2000 shop bill.

kenbiddulph

Neutral dropping is bad. I know from experience, I have seen it happen to other people's cars. So don't do it or at least know about the consequences, get your checkbook handy and then do it.

I did it once on my old Accord by accident and the tranny acted funny for days afterwards, eventually it went back to its old self but I was MUCH more careful from there on.

AC TL

its called a neutral drop...too much strain on the tranny...but hey...try it.