[rosscoe001]

Has anyone changed the Gearbox Oil inside the TCT transmission, my car turned 40k and I'm about to change the Engine Oil and Filter. From what I can make out it should be very similar to a normal Gearbox as the Hydraulic Shift Part is separate. I have read that it is sealed for life but I think a change wouldn't do any harm.

 

[Cuore_Sportivo_155]

Same oil as the manual transmissions. 1.87 litres officially, but I'd put in the full 2 litres. I haven't changed mine yet, but I did add about 0.5 litres of some heavy stuff with loads of additives....

Castrol Syntrans Mutlivehicle 75W90 API GL-4 comes recommended.

 

[David C]

Castrol Syntrans Mutlivehicle 75W90 API GL-4 comes recommended.

Are you sure that is ok?

I know the Fiat/Alfa TCT is a dry clutch rather than a wet clutch system, but the fluid spec'd by them is a specific fluid and Motul list their Multi DCTF for it (which also happens to be what I use in my DSG (wet clutch system).

 

[Cuore_Sportivo_155]

yes, both the full manual, and the robotised dual clutch (in essence another manual which can't be operated manually) get Tutela Transmission Gearforce from the the factory.

wet clutch systems are a special breed, the fluid used is more akin to .

from the tutela transmission gearforce PDS:

Expressly dedicated to the FGA transmission C 635 MT & C633 DDCT

 

[David C]

Think I'd still stick to something that meets the FIAT 9.55550-MZ6 spec.

 

[symon]

What about the Fuchs Titan Sintofluid FE SAE 75W which is recommended for the manual gearboxes when they get a bit stiff?

 

[Cuore_Sportivo_155]

if it works in the C635, it'll work in the TCT.

But stiff when cold= too high viscosity, and the Castrol is actually thinner when cold.

If the gearbox is still stiff when warm, you might use the Fuchs. The castrol will protect the gearbox from wear better should you run a bit harder or longer than typical. the thinner the fluid at operating temperature, the more chance of thermal runaway. This was the death of many C630 box in the V6 engined cars.