Lunching an autobox with hard launches

Fr0dders

Fr0dders

Fr0dders

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never having owned an auto car before, i'm not exactly familiar with them.

Can you damage the box by doing repeated hard launches the same way you can damage a clutch on a manual ?

conventional autos dont have a clutch, so it crossed my mind if this makes them more resilient to this type of abuse, or if it just knackers some other component in the gearbox instead ?
 
Cant say booting any of mine has ever done any harm, iv had auto boxes pack up but not due to that.
 
Yes I borked my Accord Coupe auto box with only 60k on the clock by constantly stamping on thye go pedal, cost me £1500 just for a rebuild, then they wouldn't even guarantee it because I wouldn't spend the extra bag of sand replacing the lifters.
 
maccapacca said:
Yes I borked my Accord Coupe auto box with only 60k on the clock by constantly stamping on thye go pedal, cost me £1500 just for a rebuild, then they wouldn't even guarantee it because I wouldn't spend the extra bag of sand replacing the lifters.
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That was just as likely to be any of the reasons autos die as from booting it.
 
define a hard launch, are we talking from idle or from higher up the rev range?
 
The hard launch is not best (imo) for most auto's, much better to plant it once rolling.

That said, I've done it many many times and not (yet!) broke my slushbox.

I know of somebody who killed a 530i Auto by building it upto 5000rpm & kocking the selector from "N" to "D".

I don't think he quite had the grasp of how to do it properly..... :D
 
Its like anything isnt it, driving a car hard wears things out faster, but booting an auto off the line is not as damaging as dropping a clutch i wouldnt have thought.
 
R420LA6X2/4MNA said:
The hard launch is not best (imo) for most auto's, much better to plant it once rolling.

That said, I've done it many many times and not (yet!) broke my slushbox.

I know of somebody who killed a 530i Auto by building it upto 5000rpm & kocking the selector from "N" to "D".

I don't think he quite had the grasp of how to do it properly..... :D
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A guy i knew years back used to do this with a 200sx. pile on rpms in N and knock it into D. i didnt think that would be possible and i didnt witness it myself, but the box was killed eventually
 
Hard acceleration from a standing start should not hurt an autobox. Holding the car on the brakes with your foot on the throttle and especially shifting from park or neutral to drive at high RPM is quite likely to cause damage sooner or later.
 
I launch my Scorpio Cosworth by standing on the brakes, getting the revs to 4k rpm and then stamping on the go pedal and releasing the brakes at the same time. hasn't done any damage yet but the Cosworths do have an additional auto cooler and more brake bands over the non-Cosworth Scorps. I only do it when on the drag strip (or a chave beside me) so it's not that often tbh. Gearboxes are only £100 s/h, so no biggie if it does die :-)

A guy i knew years back used to do this with a 200sx. pile on rpms in N and knock it into D. i didnt think that would be possible and i didnt witness it myself, but the box was killed eventually
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I used to hard launch my old Sierra by putting the box into neutral, getting to 4 k then slamming it into drive. After about the twentieth attempt the diff blew (sheared the crownwheel straight down the center) - auto box was fine though!
 
Morba said:
define a hard launch, are we talking from idle or from higher up the rev range?
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by something like this:

amigafan2003 said:
I launch my Scorpio Cosworth by standing on the brakes, getting the revs to 4k rpm and then stamping on the go pedal and releasing the brakes at the same time.
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the sort of thing you'd do on a drag strip to get a good launch or something you'd do on private land with a v box to get a good 0-60 time.
 
amigafan2003 said:
I launch my Scorpio Cosworth by standing on the brakes, getting the revs to 4k rpm and then stamping on the go pedal and releasing the brakes at the same time. hasn't done any damage yet but the Cosworths do have an additional auto cooler and more brake bands over the non-Cosworth Scorps. I only do it when on the drag strip (or a chave beside me) so it's not that often tbh. Gearboxes are only £100 s/h, so no biggie if it does die :-)



I used to hard launch my old Sierra by putting the box into neutral, getting to 4 k then slamming it into drive. After about the twentieth attempt the diff blew (sheared the crownwheel straight down the center) - auto box was fine though!
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:D

I love your style.

I do the holding on the brakes thing, but no more than say 1500rpm, then plant it once I release....
 
We (me and another apprentice) asked one of our Master Tech's this a while ago, and according to him it shouldn't in theory do much more damage that dumping the clutch in the a manual, but the issue asrises when you think about replacing damaged components. Think about it, a clutch change is a walk in the part compared to stripping down an autobox. Of course the other apprentice didn't quite understand this and thought that this meant that it was perfectly alright to rev his Ford Focus up in Netural to the limiter and dump it into drive (whilst stone cold). He did this a few times when leaving work - A few weeks later he stopped driving to work, the problem? "Gearbox issues" :D.

Saying that, I'm an absoultely massive fan of "brake boosting". Left foot on the brake pedal, right foot on the throttle, revs upto 2200RPM, release the brake and whooooosh -
The engine is under strain, the turbos are spooling so you're off to a flying start at the traffic light Grand prix :).

I imagine that the heat that is built up in the box during this process is immense (and I think many people would agree that heat is the no.1 killer of Gearbox), but jolly good fun and a great way of almost completely eliminating turbo lag in the process, and I imagine far more effective than the N to D approach?
 
When i was saying no damage i was talking about booting off from rest, not dropping it into D or holding on the brake by the way :)
 
so assuming you didnt hold it at ~ 3000 rpm for too long before releasing the brake (ie kept it to a few seconds), is it going to do more / less / the same damage than it would holding 3000 rpm in a manual and dumping the clutch ?
 
I dont know but as Joshy rightly pointed out the end results are very different.

Clutches are cheaper than auto box's.
 
I liken brake boosting it more to slipping a clutch at 3000RPM rather than simply dumping the clutch, but eitherway it's not going to do the gearbox ANY favours what so ever.

I personally never do it for a prolonged time (literally, It's a matter of building up the revs and shooting off) and no issues thus far, but I change out the ATF in my box pretty regularly and even then, it's not something that I'd recommend anyone trying.
 
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