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2015 Hyundai Sonata - Transmission issue

Q: I have a 2015 Hyundai Sonata Eco with 25000 miles on it. My problem is that when slowly starting from a stop, the transmission shudders or grabs, until some acceleration is achieved. This started very early after purchase and continues today, sometimes violently. It supposedly has a two stage clutch. It does it in all three modes; Eco, Sport, and Normal.

I have had the dealer check it three times. The first two times they said they could not duplicate it and the third time they said it was normal operation for this model.

I understand there is a class action suit filed or being filed against Hyundai for this problem.

I think it is a manufacturers defect/problem. What do you think?

Thanks for your articles which I enjoy greatly.


Does your Sonata have the 7-speed DCT transmission? I think it does. That transmission was problematic in the Tucson. Car and Driver noticed a bit of a hiccup in its testing. They thought it might be the engine. Consumer Reports also felt it in their test car. I felt and reported issues with that transmission when I tested it too. New car reviews almost never report issues like this (you never know how the prior tester treated the vehicle or if yours was a pre-production tune or if a TSB has addressed an issue). When you start seeing multiple reviews talking about a problem, the problem is real. CarTalk ran this focus story on the issue.

Let us know how this one turns out for you.

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Could be. If you want some real help from Hyundai you’ll need to bring it to their attention. The owners manual or other paperwork will tell how to contact them with a complaint that has not been fixed at the dealer level. Good luck and let us know how it goes, please.

Test drive a similar vehicule and see if it does it.It could be normal behavior for that type of transmission…a test drive will confirm this.

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Thank you but there are many complaints about this model and year as well as other models & years. Seems to be a common complaint with dual clutch transmissions. There have been several law suits filed according to an internet search. Don’t think driving another one will help.

Your Hyundai is covered by a 10 year/ 100,000 miles limited powertrain warranty if you are the original owner. If you are not the original owner,a 5 year/ 60000 miles limited powertrain warranty is in effect.Get it fixed under warranty because transmissions can get costly to fix.

Has a fix been developed for the unsatisfactory performance of these transmissions?

It’s covered but hard to do when the dealer says there is no problem or it is a normal function.


Get it fixed under warranty because transmissions can get costly to fix.

Has a fix been developed for the unsatisfactory performance of these transmissions?

There was a lawsuit for model years 2011-2014 because of premature engine failure. Has nothing to do with the problem you perceive to have.

Unfortunately that was our same experience with Hyundai when we had a warranty drivetrain problem with our Sonata. It helps them stay out of small claims court. By never admitting that you’re having a problem, it helps them avoid the “3 warranty repairs” needed for Lemon Law hearings.

Of course you could spend lots of your own money to have independent mechanics verify the problem exists, and then pay them to accompany you in small claims. They’re banking on you not doing that.

I learned that costly lesson the hard way.

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If there were a remedy available the dealers would be repairing these vehicles and not wasting their time inspecting and dismissing each problem.

Class action lawsuit;

"Our firm, ******** Law APC, along with co-counsel, is litigating a class action lawsuit on behalf of consumers who purchased or leased any Hyundai vehicle equipped with a 7-speed dual-clutch automatic transmission, including 2016 Hyundai Veloster (Turbo), 2016-2017 Hyundai Tucson (Eco, Sport, Limited), 2017 Hyundai Sonata (Eco), and 2017 Hyundai Elantra (Eco) vehicles. The lawsuit, entitled Wylie, et al. v. Hyundai Motor America , is pending in the United States District Court for the Central District of California, Case No. 8:16-cv-02102. The lawsuit alleges, among other things, that Hyundai:

* failed to disclose the fact that certain vehicles’ transmissions contain design defects in the transmission control module; and
* failed to disclose that these defects could cause failure to shift, stalling, and delayed or no acceleration, loss of power, and premature failure of the transmission’s components.

We believe that Hyundai’s advertising and marketing of the Hyundai dual-clutch transmission vehicles described above misled consumers in violation of consumer laws and that consumers who purchased and used the vehicles suffered damages based on the unexpected transmission issues and related safety risks."

Doesn’t seem to include the 1015 model

I wonder why the manufactures seem to have so much trouble with this dual clutch technology? Pretty common thing reported here, not necessarily on the vehicle , but in general. It seems (without knowing much about the design subtleties) like the dual-clutch method should be as reliable or even more reliable as a manual clutch transmission. But we rarely hear this sort of complaint about manual clutch transmissions here.

Because the DCT is conceptually at odds with the way vehicles are driven on public roads.
DCTs are more successful in racing because the pattern of use is more predictable, and smooth low speed operation isn’t important.
Creeping in stop-and-go traffic, parallel parking etc, are hard on the clutches.
Wet clutches with their cooling would be a help, but the Hyundai at least uses dry clutches, and will go into a limp mode when they get too hot.
No matter how sophisticated the trans controller is it can’t always anticipate what a street driver is going to do.
This can be a minor annoyance with a conventional auto trans, but is a real problem with a DCT because it operates sequentially.

Taking the 7-speed as an example, there are two gear sets.
One is gears 1, 3, 5, 7; the other 2, 4, 6, reverse.
One of the two clutches selects one of the gear sets at any given time.
The other gear set is set up for an anticipated gear change, when one clutch releases and the other engages.

Suppose you gently accelerated up into 4th gear, then you go onto a highway ramp and punch the gas.
But the trans has set the next gear shift up for 5th gear, anticipating more gradual acceleration.
But what you really need is a downshift to 3rd.
What you get instead is limited power and delay.

Some say the problem is drivers need to adjust their driving style to suit the DCT.
But I think the vehicle should accomodate any reasonable driving style for it to be truly automatic.

I’ve been driving mostly manual cars for ~35 years and recently bought a 2017 Tucson, my first automatic since my 1985 Accord was stolen in 1993.
When I did research on the Tucson I saw that ~90% of the complaints on were related to the DCT, so I got the conventional 6-speed auto.
I don’t care that it gets 2mpg less in the city or that it’s about a second slower to 60mph.
I care more that it takes off every time I push the go pedal.

Good explanation. Is there a design change possible so when the correct next gear is 3 rather than 5 as you post above , it could do that instead? Or is there something fundamental in the DCT design that makes this impossible or impractical?

Why is this a problem for a DCT? My single clutch manual transmission Corolla can easily be shifted into either 3 or 5 from 4th gear depending on what’s needed at the time.

There’s a substantial time delay for the DCT to switch between 5th and 3rd (in preparation to shift from 4th).
With your manual you know where you’re going ahead of time.

Sounds like this DCT technology just isn’t ready for prime time.

Our intern at work had her 2015 Focus transmission replaced twice during her 3 year lease. I’ve been saying for a couple years now that Ferrari and VW/Porsche seem to have gotten their DCTs right, but everyone else should probably just give up on them. At one point it was thought these were the future of all automatic transmissions, and none of the automakers wanted to be left behind by not developing their own.