Engine oil change

Oil + oil filter change. Full synthetic Wolf Vitaltech 5W-40 (VW 502 00) engine oil has been used.
For the details click here.

Odometer: 67,500 km.

Performance clutch

At the same time, while changing the gearbox's differential I decided to replace the stock clutch reinforced one that holds more torque amount.

I chose the South Bend Stage 2 Endurance clutch kit with the single mass (8.6 kg) steel flywheel.
Manufacturer guarantees that it will hold up to 610 NM of torque, that is actually ~15% more than I need. Good to have some durability reserve. :-)

The new clutch kit

 Gearbox was extracted and the access to the clutch opened.

The stock clutch in place

Stock clutch + flywheel removed & inspected

The stock clutch used by SEAT in Leon Cupra MK2 is exactly the same clutch as used in Audi S3 8P or Golf R VI. The new one that I ordered from ECS tuning was for Golf R (SEAT isn't officially distributed in the USA, therefore doesn't appears in theirs cars listing), but thanks to VW and its compatibility: I may order many of spare parts for my car from there. :-)

You may see that this is only some reasonable amount of wear on it. So my conclusion that the stock clutch is good enough if you not going into aggressive accelerations from 0 km/h.

Meanwhile, when original flywheel was removed, some little problem was detected: the small oil leakage under the crankshaft gasket:

Crankshaft gasket "sweat"

This is the well known problem of 2.0 TFSI EA113 (also for 2.0 TSI EA 888 gen 2) and many others engines. So if you replacing a clutch, it worth to check this gasket too and replace it if needed.
You really don't want to remove again gearbox and clutch afterwards - only for gasket replacement. :-)

First of all, it's very important to perform clutch "bedding in" as it required for normal clutch operation. I did it according to the manufacturer instructions during the first 1200 km.

So how this clutch feels when it on car?
Well, I love how it works. :-) The pedal feel is near the stock: it's only a little bit harder for press, but not much. The clutch engagement is quite smooth.

Regarding transmissions noises:
I heard many complaints from people that starting to hear transmission noises (this is almost always an issue when using a single mass flywheel), but surprisingly for me, there was almost no noises at all, even if air conditioner is in action and them almost not-audible. They are not spoiling the overall car's comfort, thanks to well-designed clutch disc and relatively heavy flywheel.

But after all, if you specially listen for them, you will hear them. :-) Transmission noises are exists in very small amount on idle or when accelerating. This fact should be taken into account when upgrading you stock dual-mass flywheel to the single mass flywheel.

The main reason for making a such upgrade - is to avoid the dual-mass flywheel internal elements weariness (springs, gears, e.t.c.), which usually leads to different noises and then to its replacement after ~90,000 kilometers (the distance is varies for different vehicles).  Single mass flywheel has very simple build with no internal elements at all, so it simple doesn't has this problem by design.

Odometer: 67,300 km.

Wavetrack LSD

It's not a secret that powerful FWD cars are always struggling to effectively put their power onto the road. And this is almost impossible with open differential, that always puts the power where "easy to put it", i.e. onto the wheel, that in the slippery surface or in the air. It will never put the power onto the wheel that under greater load than other in the same axle.

The LSD (Limited-slip differential) will do exactly the opposite: it will put the power, where its needed, i.e. onto the wheel that has better traction in specific moment. This is exactly what we need on the slippery road or at high speed cornering.

Wavetrack LSD has been chosen for this purpose.

Complete LSD conversion kit

Some pictures from install:

 02Q 6-x speed gearbox prepared

Open differential (at the bottom) vs Wavetrack LSD

Now the cornering became the different story: under acceleration the car is simply sticks the desired trajectory while cornering. Indeed, this allows to achieve very impressive cornering speeds and made the car's behavior more safer and predictable on the slippery road.

It's maintenance free and will perform a lifetime of service without any touch. Also, it offers improved no-load performance when compared to other helical gear differentials on the market.
You may read more details here at the product web page.

Of course, transmission oil has been replaced again. The same oil has been used as in previous replace (Valvoline SYN POWER 75W-90) as it is compatible with LSD differential. But this time it has been filled without any oil additives, that lowers friction within the gearbox. This is according to directions from LSD manufacturer (Wavetrack).


Odometer: 67,300 km.