Fiesta ST Mk8 OEM LSD gearbox swap – open diff to factory LSD

[Kanak14]

Hello everyone,

Sorry in advance if there is already a thread covering this topic. I did have a look around but couldn’t find anything specific, so I’m starting a new one.

I have a 2019 Fiesta Mk8 ST, fully optioned the way I wanted it, but unfortunately it didn’t come with the Performance Pack. I can live without the shift lights and launch control (although they would be nice to have), but the main thing I’m really interested in is the Quaife LSD.

I’m currently looking at buying a complete used gearbox from a Performance Pack car that already has the LSD installed (K1BR-7002-BHB) and swapping it into my car. I will be taking the car to a professional workshop to have the swap done properly.

What I’m most concerned about is whether everything will actually fit and work together properly. I’m worried about compatibility (driveshafts, mounts, etc.) as well as drivetrain differences that might affect the swap.

Before I go ahead with it, I wanted to ask if anyone here has done something similar or knows what’s involved.

Is this a straight plug-and-play swap, or will I need any coding, ECU/TCU adaptation, or additional parts (driveshafts, mounts, sensors, etc.) for it to work properly?

Any advice or experience would be greatly appreciated.

 

[madhatter]

the Quaife is a mechanical diff, and does not have any wiring connections. Aside from it being shimmed properly, you shouldn't need to do anything special if you don't mix/match model years. if you want to turn off the E-diff, you'll need to get into the ECU, but the quaife should mitigate the brake based diff and you could leave it. People swap just the diff into the 6 speed gear boxes all the time.

 

[M-Sport fan]

Since this is a Mk8 Euro/rest of world Fiesta ST Kanak owns/is referencing, yes, the whole transaxle assembly should just bolt right up to the Ecoboost 3 banger's bell housing in a non Performance Pack FiST.

Ford would definitely not spend the coin to upgrade to different (or stronger) axles/half shafts just for that optional package, and yes, there would not be any electrical connections/sensors exclusive to the mechanical, Torsen type, Quaife diff.