How well will a DCT survive stop and go traffic

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WhyMe

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Was at the Hyundai dealer looking for a car for my son to drive to school at UW. Was looking at the iconiq hybrid and the gas mileage was 55 mpg. I drove it and it seems ok.

The one thing is that it has a DCT in it. My son will be doing a lot of stop and go traffic when heading to a school . I am concerned of the durability of the DCT to survive long term stop and go use.

So how well do they last in stop and go situations
 
Doesn't Hyundai provide a 10 year/100,000 mile warranty? But, better have all services done by Hyundai so that no questions arise.
 
Originally Posted by dbias
Is it a wet or dry clutches?



Good question, the wet clutch design seems to hold up far better than dry...

I THINK Hyundai/Kia use wet design too.
 
Originally Posted by AC1DD
Originally Posted by dbias
Is it a wet or dry clutches?



Good question, the wet clutch design seems to hold up far better than dry...

I THINK Hyundai/Kia use wet design too.


Yes wet clutch handles the heat from stop and go better. However drivers really need to understand the dual clutch concept and drive accordingly. No one who knows how manual transmissions work would use the slipping of the clutch to hold a manual transmission vehicles on a hill at a red light, but those who are driving a DCT vehicle may do it without a second thought. MY experience with VW and Audi DSG has been great and i do my own fluid/filter changes religiously AND make sure wife and kids know how to use them. VW calls them "Automated Manuals" and i think that is a good description.
VW/Audi DSG also have some tricks that others auto makers may also, but i'm not sure .....such as tapping the brake as you start downhill to let the DSG know to hold the present gear to use the engine braking instead of riding the brakes, and as soon as you want to coast lightly tap the accelerator and it will downshift and glide faster.
 
Hyundai uses a dry clutch. I have one. No problems with it and an excellent warranty.
 
Verify w/the dealer if the transmission has any special maintenance needs and if so, how much it cost. When I was looking at a VW TDI, the DCT trans required specific maintenance -I believe every 30k or 40k miles and the dealer cost was $450.


Ray
 
Originally Posted by Kira
What are some of those considerations/driving habits when driving a DCT?


No creeping and crawling. If you're in stop/go traffic, don't inch along slowly but rather try to move in discrete distances of at least 1 car length at a time.

BTW: the reason I purchased a Mazda3 instead of a VW TDI was because of the higher maintenance transmission in the VW. The Mazda3 has a 6 speed auto that has a lock-up torque converter. When speeds are stable, the torque converter has a clutch that locks up. When transitioning thru gears, it unlocks and lets the converter handle the transition smoothly. It has a long history of being pretty bullet-proof and needs no special maintenance.

Ray
 
Originally Posted by zzyzzx
I would be avoiding any vehicle with a DCT or CVT, without regard to year of manufacture or make of vehicle.



When it comes down to it, I'd forgo the DCT and get a manual transmission.
 
Originally Posted by zzyzzx
I would be avoiding any vehicle with a DCT or CVT, without regard to year of manufacture or make of vehicle.


already did this when i bought a 2019 Tucson for my daughter last month. it seems difficult to find a vehicle without a CVT or DCT these days.
 
Originally Posted by RayCJ
Originally Posted by Kira
What are some of those considerations/driving habits when driving a DCT?


No creeping and crawling. If you're in stop/go traffic, don't inch along slowly but rather try to move in discrete distances of at least 1 car length at a time.

BTW: the reason I purchased a Mazda3 instead of a VW TDI was because of the higher maintenance transmission in the VW. The Mazda3 has a 6 speed auto that has a lock-up torque converter. When speeds are stable, the torque converter has a clutch that locks up. When transitioning thru gears, it unlocks and lets the converter handle the transition smoothly. It has a long history of being pretty bullet-proof and needs no special maintenance.

Ray




My understanding is that the TC locks up around 5mph and the transmission is pretty much direct.
 
Re how to drive/svce. a DCT: yes, don't creep but go in discrete distances; don't hold it on a hill with throttle; don't stay stopped with your foot off the brake (i.e. keep your foot on the brake 'till ready to go); expect a 'wee pause when you get back on the throttle to go (it is NOT an instant start-up). Change fluid for trans religiously; use OEM fluid. And lest your son wants to play wanna-be racer in manual mode - realize that downshifting at high speeds (for the gear selected) is like downshifting on a manual without double-clutching / rev-matching: it will wear out the synchro's early - just like a manual will... 'cuz it IS a manual. Driven like Grandma, I suppose it will last. I'm just not sure that it will when driven with exuberance for the reason I mentioned. Driven well, nothing lasts like a plain 'ole manual but I'm in the minority liking manuals.
 
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The VW Jetta I drove with a TDC rev matched all downshifts, so it should not be a problem, but if Hyundai uses dry clutches, they are much less tolerant to heat than wet clutch setups.

If there is any lesson to be had, just look at Ford. I highly dount Hyundai made a better unit.
 
Does the Ioniq have paddles?

Good driving from a DCT REQUIRES using the paddles! Don't just keep it in D. Shift it manually
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Fluid changes every 30k or less. Amalie makes a good DCT fluid at a fair price. Buy it by the case on Amazon.
 
Originally Posted by KrisZ
The VW Jetta I drove with a TDC rev matched all downshifts, so it should not be a problem...


The fact that a DCT rev-matches (all of them do) only saves the clutch(es); it does zero for saving the synchromesh.

All DCT's, i.e. from all mfr's, make their shifts "single-clutching" (so-to-speak, if you could liken it to a non-automated single clutch manual transmission). Now they are variously equipped with double-cone or in some cases (or for some gears... the lowest of the gears)- with triple-cone synchro's. However, they do not double-clutch like a skilled driver can, with a manual 'box (where the "to-be-shifted-into" gear is sped-up while in neutral, clutch pedal out, to perfectly match up the synchro splines.... so no- or very little synchronizer action is actually necessary). Little synchro-action, little wear.

The other thing that a DCT does - is the shift mechanisms move with lightning speed. So though the synchronizers are quite strong and effective, it's like every shift the transmission makes is a speed-shift. Can you imagine a manual transmission car, where every last shift is executed as a speed-shift... both up-gears and gearing-down (which is really hard on the synchro's)!

Now a certain amount of this duress, and the capability to withstand it, is designed-in. But what will the life-expectancy be with someone who aggressively downshifts (at considerable speeds) in manual-mode, all of the time?

For me, I will just continue to double-clutch down, and generally lazy-shift... to gain long life out of my manual 'boxes.
 
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I will grant you, though, that the DCT typically goes from one engaged gearset to the other gearset... and so it COULD afford to make the shifts slowly when going up-gears. However, when you are in automatic and you press the throttle, some of the time in reaction to your demand for acceleration it wants to go down two gears... and in doing this, it has to shift twice as it were. From the active gearset, to the opposite gearset (not sure which gear it engages... and it really does not matter) and then last of all - back to the original gear-train... which makes it two gears down. So in order for that automatic shift to not be really long shift-duration, it has to make all of its (internal) gear-switching very quick.

So what I'm saying, here, is that all DCT (internal) shifts are lightning quick, even if this is not necessary upshifting.
 
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Cdn17Sport6MT beside the fact that most people don't double clutch in manual transmissions and still get high mileage out of them, I don't think you understand how dual clutch transmissions work.

The reason they are dual clutch is because the unit is essentially two transmissions in one. One takes care of gears 1,3,5 and the other 2,4,6. When the first one is in 1st gear, the second one already has the 2nd gear selected and only its clutch is disengaged.
So when the gear change happens, the first clutch disengages and the second one engages, that is why the hear changes are so quick.

There is no forcing of synchronizers.
 
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