DCT Failure

doublespaces

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Apparently this was on a Z4 in Russia making a lot of power, launch control and slicks.

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martymil

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They are a fast shifting box with the right software but as soon as you turn the power up they dont last long.

I cant believe there is minimal options for after market gearboxes for these cars.

A nice and quiet sequential box is what I'm after.

It will happen eventually.
 

martymil

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Its not the first time I've seen this type of damage in a dct box, its not common but it happens.

Its not the hp that breaks these but the lack of traction, axel tramp and sticky tyres at elevated hp levels.
 

martymil

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Nothing that's documented on internet workshops don't want to advertise broken gearboxes as it turns customers away until

1 they have a solution that they want to share
2 they have a solution thats a cheap fix

They rather keep their mouth shut and take peoples money as its more work for them
 

aus335iguy

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I find that strange we don’t see pics. N54 folks are usually the first to complain on forums and social media about stuff like this. As per the Russians they’re boasting they broke one.

Meanwhile these things are backing LS’s and 2j’s happily in some cases. It’s still the strongest of the standard gearboxes in my opinion.
 

martymil

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Im not saying they are not strong, commenting that's its not the first time this has happened.

If this was well documented how many people do you think would modify their dct cars, most tuners would loose half their customer base.

Its not widespread but has happened amongst other dct issues.
 

N.Ceder

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The dct gearbox is strong, but shit will go sideways if you get wheelhops and stuff like that.

We have pushed 1400Nm using the same geaebox in dyno, maybee 400 runs during development, and trashed tires for 2000USD during burnout test, launches.

So, if one guy in russia breaks his gearbox, that does not mean this one is weak.
More likely there was not enough oil in the gearbox or any other abuse.
 

martymil

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Wheel hop will destroy any gearbox no matter how strong and these cars are quite susceptible to this, this is the most likely culprit especially when on slicks unless you take steps to eliminate it.
 

N.Ceder

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Wheel hop will destroy any gearbox no matter how strong and these cars are quite susceptible to this, this is the most likely culprit especially when on slicks unless you take steps to eliminate it.
Exactly, the DCT is strong. Period.
 
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martymil

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Strong but not indestructible, not many people have addressed wheel hop on these cars amongst other things to prevent damage,

All they want is power for as little money as possible and cry when something breaks.
 

aus335iguy

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For what you can buy on the used market here for 1500 AUD This is the closest thing to perfect for me in a gearbox.
Fast shifting
Strong enough to handle 1000hp +
Good enough for me to use in stop start traffic/let my wife or kids drive it.

People are already using them on other platforms for this reason.They’ll start getting more expensive once we can do custom flashing and if youre @N.Ceder, the guy from MaxxEcu... Thanks for that!
 
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martymil

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Im waiting for a low km s55 box to come along, as it will be a straight bolt in to the 1m I believe, the factory s55 flywheel is a direct fit.

Flash it with the gts tune and you have a monster.
 

aus335iguy

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You might be better off grabbing an n55 box, and just getting the flywheel and other bits like the cooler, and ancillaries elsewhere. Same box, beats waiting.
 

aus335iguy

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I know it has different ratios. I remain unconvinced on whether its actually beefier.
Larger bearings and different gear widths measured would constitute proof. I haven’t seen evidence other than words.
 

N.Ceder

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Strong but not indestructible, not many people have addressed wheel hop on these cars amongst other things to prevent damage,

All they want is power for as little money as possible and cry when something breaks.
For what you can buy on the used market here for 1500 AUD This is the closest thing to perfect for me in a gearbox.
Fast shifting
Strong enough to handle 1000hp +
Good enough for me to use in stop start traffic/let my wife or kids drive it.

People are already using them on other platforms for this reason.They’ll start getting more expensive once we can do custom flashing and if youre @N.Ceder, the guy from MaxxEcu... Thanks for that!

Yupp, thats me.
 

N.Ceder

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We bought ALL clutch kits out there for this gearbox, we have pushed so much torque thru it, we have tested different clutch pressures, we have cracked the CAN communication, cracked the TCU firmware, teared apart like 5 gearboxes.

Up and down with Mustang DCT gearbox like 25 times not, just to bring our DCT customers running our MaxxECU the best option and information, when we free of charge, as a software update bring it to our MaxxECU as an CAN Control option.

So if I say this gearbox is strong, and that both SSP and Dodson makes good clutches, you better believe me, otherwise I dont know what to do with you ;-)

All it took, was a madman from Sweden, a mustang, a DCT gearbox, motivation as hell, countless of non sleeping hours, and a few litres of Pepsi Max, and myself as a developer/owner of MaxxECU to get it done.

But it is kinda fun to do shit that noone had ever done before ;-)
 

stevieturbo

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So is there a DCT box that is known to be stronger ?

Is the 1:1 5th or the 1:1 7th the stronger box ?

I presume that 1:1 7th is a direct drive through the box...so in theory at least, that gear should be the strongest option ? Usually overdriven gears tend to be weaker due to sizing.