MajorCommonTransmission

Hyundai i40: 7-speed DCT (D7UF1) clutch-pack wear and engagement faults on 1.7 CRDi automatics

7-speed DCT (D7UF1) clutch-pack wear and engagement faults on 1.7 CRDi automatics is a common transmission fault on the Hyundai i40 on the 2015–2019 cars, and we rate it major. Putting it right costs $2,500 to $5,500 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 5 documented faults on the Hyundai i40.

Vehicle: Hyundai i40
Engine: 1.7L
Years: 2015–2019
Fuel: diesel
Gearbox: dct
System: Transmission

This page covers the Hyundai i40 as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Hyundai i40 faults5 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Clutch yet. We would rather show none than show a picture of a different part.

What goes wrong

Facelifted diesel i40 automatics use Hyundai's 7-speed dry-clutch DCT, and it is the weakest part of the car. Documented problems include take-off shudder, hesitation and overheating in stop-start traffic, harsh or banging shifts, and worn clutch packs that eventually refuse gears — first-gear failure with fault code P0921 is frequently reported. Clutch-pack replacement is a four-figure job and control-unit or mechatronic problems cost more, so a slow-traffic test drive is essential on any DCT car. Manual and earlier conventional-automatic i40s avoid this gearbox entirely.

What you would notice

Shudder or jerking pulling away, worst on hills
Hesitation then a bang engaging first or reverse
Harsh low-speed shifts in traffic
Transmission overheat warning in slow traffic
Fault code P0921 / refusal to engage first gear

How to check it

Where to look. 7-speed dual-clutch automatic transmission; symptoms are felt in take-off and low-speed shift quality and shown as dash warnings

Structure the test drive around the gearbox's weak spot: spend at least 15 minutes in slow, stop-start driving, creeping repeatedly from rest, and feel for shudder, delayed engagement or banging shifts. Do a hill start and feel the take-off quality. Watch the dash for any transmission temperature or check warnings during the slow-traffic section. From rest, select reverse and then drive several times — engagement should be prompt and smooth every time. Ask whether the DCT clutches have been replaced, whether any software updates were done, and request the invoices. If a workshop inspection is possible: read the transmission control unit for stored codes (including P0921) and check the clutch adaptation values against wear limits.

Parts involved: Clutch.

What it costs to put right

$2,500 to $5,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“Have the DCT clutch packs ever been replaced, and at what mileage?”
“Has it ever refused to engage first or reverse, or shown a transmission warning?”
“Has the gearbox software been updated by a dealer?”

Now check the Hyundai i40 you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in the sources below. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them.

Hyundai Forums thread: '2017 i40 Shudder' — 1.7 diesel DCT take-off shudder
Hyundai Forums thread: 'i40 2016 Automatic — sometimes shudders on takeoff'
ASR Gearbox Repairs: Hyundai i40 common gearbox problems (7-speed DCT)
carchecker.pro Hyundai i40 VF report — DCT clutch-pack failure, P0921 first-gear fault

Hyundai i40 buyer questions

Is 7-speed dct (d7uf1) clutch-pack wear and engagement faults on 1.7 crdi automatics serious on a Hyundai i40?

We rate it major and common on the Hyundai i40. Facelifted diesel i40 automatics use Hyundai's 7-speed dry-clutch DCT, and it is the weakest part of the car. Documented problems include take-off shudder, hesitation and overheating in stop-start traffic, harsh or banging shifts, and worn clutch packs that eventually refuse gears — first-gear failure with fault code P0921 is frequently reported. Clutch-pack replacement is a four-figure job and control-unit or mechatronic problems cost more, so a slow-traffic test drive is essential on any DCT car. Manual and earlier conventional-automatic i40s avoid this gearbox entirely.

How much does it cost to fix on a Hyundai i40?

$2,500 to $5,500 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Hyundai i40 years are affected?

Our research records this fault on the 2015–2019 Hyundai i40. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.