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Discussion Starter #1
Does anybody around here happen to know how much strain/risk is added to the A8 automatic transmission if launch control is used? Obviously doing launch control is more wear and tear for the transmission than not using launch control - but so is driving in in WOT and high RPMs for the engine. I'd like to know if it will significantly reduce the life of the transmission or if it will just be a bit more wear and tear which comes with driving the car hard.

While I like to have fun with the car I don't want the transmission die prematurely on me at 60k miles or so because I did launch control every now and then.

Any input is appreciated!

Thanks All!
 

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A very good question, I'm taking the 5th on it but will say this, there are two components on at the same time that causes the locking effect, a massive hydraulic bind if you will, release one via solenoid control and you're gone
 

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2020 Dodge Challenger Hellraisin Scat Pack
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Does anybody around here happen to know how much strain/risk is added to the A8 automatic transmission if launch control is used? Obviously doing launch control is more wear and tear for the transmission than not using launch control - but so is driving in in WOT and high RPMs for the engine. I'd like to know if it will significantly reduce the life of the transmission or if it will just be a bit more wear and tear which comes with driving the car hard.

While I like to have fun with the car I don't want the transmission die prematurely on me at 60k miles or so because I did launch control every now and then.

Any input is appreciated!

Thanks All!
The wear/tear on the transmission when driving the car at WOT or at high RPMs is not the same as when using launch control.

If you are efficient with launch control this works to minimize wear/tear.

Here's a video that I think shows a pretty efficient technique. Jump to the 1:00 mark.


I've never used my Hellcat's launch control and I may not ever. Well, I might use it. I watched a Porsche tech demo the launch control that the PDK transmission supported and the take off was just awesome. Wow. I think I'd like to experience that with my Hellcat at least once.

Anyhow, launch control still requires the transmission gets the car moving while being supplied all the HP and torque the engine can produce. This just naturally has to subject the transmission to well, more wear and tear.

There is a trade off. Every use of launch control takes a toll on the transmission. The question is how much of a toll. I can't answer that. Kind of like trying to map track miles to street miles. Is one track mile equal to 10, 50, 100, or even more street miles?

Is one launch control use equal to 10 "normal" take offs, 50, 100 or even more? I don't know. Maybe Dodge knows, has some idea, but it ain't talking.

I have not seen anything from Dodge that suggests one needs to limit the use of launch control. (Porsche claimed there was no mechanism to count the number of times launch control was used. I read some reviews of various cars with this feature being launched time and time again with no apparent signs of distress from the transmission. However, we don't know how the transmission fared as time progressed. Also, the PDK transmission is different than the automatic in our cars. The PDK uses dual multi-plate wet clutches and while the clutch that services the odd gears: 1, 3, 5, 7; slips upon launch it does so bathed in transmission hydraulic fluid. There are a number of plates to absorb the wear and tear too.)

Just a WAG on my part but I'd say the use of launch control is probably not going to shorten the service life of the transmission in any substantial way. Be sure to follow the guidelines and avoid doing this over and over again. Might be interesting to have the transmission fluid temperature display showing and see how much the fluid heats up from using launch control. If it is negligible that's a good sign. If it zooms up, not so much.

There is a caveat though. Like an engine a transmission is only as strong as its weakest part. Just normal usage even the occasional WOT or high RPM usage would probably be unlikely to cause this weakest part to fail. But the use of launch control might.

If one uses launch control occasionally it might be a good idea to have the transmission fluid and filter service done more often.
 

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Discussion Starter #4
Just found this educational video on YouTube.

https://youtu.be/Mig14z78MbY

Apparently there is quite a bit of heat created during the process of stalling. What I got out of it is, yes, it's not good for your torque converter due to the torque being converted into heat and not motion during stalling, but if you have to do it:

1. Don't stall for too long as more heat builds up the longer you go.

2. Don't do launch control in succession cause the heat should have increased significantly after the first launch.
 

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There is no stalling with the Dodge Launch Control, the transmission runs in neutral at your preset rpm with no strain or heat on anything until you release the brakes then it's gone. Works nice and smooth with no obvious jerking or abuse, I'd say it's easier on a transmission than powerbraking. If you are getting a powerbrake or wheelspin while trying to use launch control you're not doing it right, this factory LC system works great and is a lot of fun.



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In neutral??? Then how does it go into drive without blowing up??? Doesn't it lock first and reverse together to stall/lockup the trans and when the button is released, reverse drops out??? IDK..................
 

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Discussion Starter #7
In neutral??? Then how does it go into drive without blowing up??? Doesn't it lock first and reverse together to stall/lockup the trans and when the button is released, reverse drops out??? IDK..................
There's no 'button' though. You just release the brake and then the car goes. I would think it's more of a glorified brake torqueing that holds the throttle for you at the desired RPM number.
 

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No it's not brake torquing or powerbraking, it's between gears or however they do it but it is like the the trans is in neutral with no strain on the car at all. Don't think it's 1st and Reverse, it's first and another forward gear shift solenoid engaged at the same time and this causes the trans to act like it's in neutral. The engine goes straight to your preset rpm and holds, then the dash display says launch control engaged release brakes, when you release the brakes the other trans shift solenoid releases leaving only 1st and you're gone!. Again there is no powerbraking, strain or wheelspin if you do it right, it's just like revving in neutral.until.you release the brake.


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No it's not brake torquing or powerbraking, it's between gears or however they do it but it is like the the trans is in neutral with no strain on the car at all. Don't think it's 1st and Reverse, it's first and another forward gear shift solenoid engaged at the same time and this causes the trans to act like it's in neutral. The engine goes straight to your preset rpm and holds, then the dash display says launch control engaged release brakes; when you release the brakes the other trans shift solenoid releases leaving only 1st and you're gone! Again there is no powerbraking, strain or wheelspin if you do it right, it's just like revving in neutral until you release the brake.
Good explanation here Slidd. I'd like to see a Scat Pack with a Shaker hood in launch control. Based on what you're saying, the shaker would torque to one side under the strain while power braking the engine. However, under launch control, if you are right, the engine would not torque over to the side until the brake was released and launch control put things in motion.
 

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There is no stalling with the Dodge Launch Control, the transmission runs in neutral at your preset rpm with no strain or heat on anything until you release the brakes then it's gone. Works nice and smooth with no obvious jerking or abuse, I'd say it's easier on a transmission than powerbraking. If you are getting a powerbrake or wheelspin while trying to use launch control you're not doing it right, this factory LC system works great and is a lot of fun.



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Slidd, what RPM setting are you using with LC? Hate to say it, but I haven't tried it out yet!:surprise:
 

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In neutral??? Then how does it go into drive without blowing up??? Doesn't it lock first and reverse together to stall/lockup the trans and when the button is released, reverse drops out??? IDK..................
You are thinking "trans-brake" like the Demon has. Launch Control just holds the specified RPM against the brakes and when you let the brakes go, it goes to WOT. I would think it creates some heat in the Torque Converter, but you are not holding it against WOT like a trans-brake, so I doubt it will cause any trans issues.
 

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Slidd, what RPM setting are you using with LC? Hate to say it, but I haven't tried it out yet!:surprise:
I think I read yesterday that the RPM isn't selectable with the auto but is with the manual.

SLIDD will know more about that than I do.
 

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I think I read yesterday that the RPM isn't selectable with the auto but is with the manual.

SLIDD will know more about that than I do.

Launch Control is locked out for the first 500 miles. According to the manual, it's active for both the 6M and A8 cars.


My problem, as I don't have a track near me, is finding a safe paved place to try this out. Varying the launch RPM could be heaven, or it could be hell! LOL


Unfortunately, I still have the stock tires on mine, so I'm not sure what the best setting would be to even start off with, after I find a place to play with it.
 

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I tried it out a couple of times with the stock tires and all it did for me was give me excessive wheel spin. I would suggest trying at as low of a setting as possible to start with. Maybe it is the roads around here, but I have a real problem with traction if I go WOT from a stop and I need to use partial throttle at launch to get a good 0-60 time. Launch Control is too aggressive for me on the roads that I tried it on. I might play around with it some more once the weather warms up. It is only 34 degrees here today, lol.
 

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Discussion Starter #15
No it's not brake torquing or powerbraking, it's between gears or however they do it but it is like the the trans is in neutral with no strain on the car at all. Don't think it's 1st and Reverse, it's first and another forward gear shift solenoid engaged at the same time and this causes the trans to act like it's in neutral. The engine goes straight to your preset rpm and holds, then the dash display says launch control engaged release brakes, when you release the brakes the other trans shift solenoid releases leaving only 1st and you're gone!. Again there is no powerbraking, strain or wheelspin if you do it right, it's just like revving in neutral.until.you release the brake.


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Thanks for the input. Out of curiosity, what source did you get the information from?
 

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2000 rpm is the highest I can set it to with the stock 275s or it will spin at the start and not engage and let me clarify my previous posts. Part of the procedure when you are holding the brake with left foot and then quickly going to full throttle is that there is a beief initial torque surge to the tires. As long as your launch rpm is not set too high, then the launch system will engage and now the engine runs totally free with no powerbraking or drag from the torque converter at all, it's just the first little surge which I guess is the way the system checks to see what kind of traction you will have versus the launch rpm. If you set the rpm too high, the system will not engage and it will be like a powerbrake. This is telling you to lower your set launch rpm. Again 2000 rpm or close to is ideal for my setup, it works like a true transbrake and you blast away with just the right amount of wheelspin and it really goes. Just keep your foot to the floor and let the system do it's thing or it will disengage, also keep a good pressure on the brake too or it won't set. It took me a few times messing around with it to get the hang of it but it's a blast when you get it!

The owners manual should cover it, if not download the SRT owners manual or SRT supplement and it's in there.



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Isn't the torque converter being spun? Pretty sure it is as I know of no mechanism present that disconnects the torque converter from the engine. The transmission is receiving torque even if the transmission is in some mode where it can't turn, in which it is locked.

When the transmission is then unlocked there is a surge of torque through the transmission and the first gear clutch band is tightened around its drum but at a higher the normal take off speed which adds to the wear and tear on this assembly. Then "just" the normal wear and tear of a hard acceleration up through the gears occurs.

The use of launch control has to add to the wear and tear on the transmission. Just really a matter of how much. And not knowing this how much of a gamble one wants to take with the transmission accepting this as a cost of sorts in using launch control vs not using it.
 

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Good explanation here Slidd. I'd like to see a Scat Pack with a Shaker hood in launch control. Based on what you're saying, the shaker would torque to one side under the strain while power braking the engine. However, under launch control, if you are right, the engine would not torque over to the side until the brake was released and launch control put things in motion.
I will have to pay attention to this when I get my SPS out of hibernation - unfortunately, here in NE Ohio, we got more snow today! I've used launch control with success both on the street and at the track. But, honestly, haven't paid attention to what the shaker is doing. Only problem with using it at the track, if you do not stage first, you don't have enough time to actually cut a decent light. You'll be sitting still at green looking like a fool. Ask me how I know...:laugh2:
 

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Discussion Starter #20
Guess next time I use it I will check the transmission temperature before and after. If there's a significant rise afterwards, then it's clear that there is quite a bit of extra stress on the transmission.
 
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