Before I begin I would like to reference Rodmoe's thread he made awhile back. http://www.fiestastforum.com/forum/threads/1365-LSD-Installation-Thread His thread was the only thing I had for a reference at all before undergoing this installation. There was however no information about the final drive and everything that was required for installing that unit. Therefore it took me 1 month and 2 weeks to finally gather all the materials I needed for the final drive while the transmission was apart. I hope to save all of you time by laying out everything I purchased as well as having the installation how to videos for you to follow.
Interesting finds:
I found that the final drive ratio, even though it is sold by Pumaspeed or Sico Developments, are parts made from Ford UK. Another note is UK part numbers do not match USA part numbers and this made a little bit of confusion when trying to search for certain parts. Another point I would like to highlight was Rodmoe noted he did not have to change the shim for his Quaife Diff and I didn't have to do so either with my Wavetrac. This could either be a great coincidence or the LSD's are made so well into spec that there is no need for that step.
LSD Installation prep:
I opted to purchase the diff installation kit through Mountune that did not include the loctite. I purchased my loctite through amazon for a much less expensive rate. I bought 271 and 515 Loctite. Other things I purchased for taking the transmission apart was a new clutch slave cylinder through Tasca as well as new case bolts. Tools I purchased for this project was a bearing installation kit from Harbor freight, a micrometer, and a seal puller.
Final Drive Installation prep:
I would purchase the Mountune diff kit as you will be replacing the ring gear as well as the reverse gear shaft and the output shaft. When ordering the kit make sure to select the option for the main pinion bearing. This bearing you can not order in the USA as Ford does not make the part here state side. The other thing is make sure you get everything in your kit as when I ordered mine the main pinion bearing was missing. Although PumaSpeed quickly corrected this and the new bearing was at my front door in 3 days from the UK! Next you need 3 more bearings and a retainer bolt for the output shaft. I will list part numbers/links further below. I also highly suggest finding a transmission shop to replace and swap the gears once you have them removed from the transmission. The added cost for myself was $136 out the door to have a shop do this process. As simple as all these parts may seem now that it is laid out, no one knew which parts went to which shaft so I went through the process of ordering all the bearings and returning the incorrect ones.
Part numbers/links:
Mountune Diff Kit http://www.mountuneusa.com/ATB-Differential-Installation-Kit-Fiesta-ST-p/2364-atb-hw.htm
Loctite 271 thread locker
Loctite 515 Gasket maker
Clutch slave cylinder DG9Z-7A564-B
Case bolts W500311-S437
Pumaspeed final drive http://www.pumaspeed.com/product-Ford-Fiesta-ST-180-EcoBoost-431-Final-Drive_16814.jsp
or Sico Final drive https://www.sico-developments.co.uk...1-final-drive-replacement?variant=12732727812
Bearings for output shaft and reverse
AV6Z-7025-B
AV6Z-7025-A
DV6Z7065-A
Retainer Bolt AV6Z-7049-B
Installation notes:
Puller the axles seals out before removing the new old races or the differential bearings. There is a groove in the house to allow a flathead screwdriver or chisel to hammer on to remove the races. It helps to have a buddy work with you! I used a Vice to hold the ring gear in place as I torqued the new bolts to hold the new LSD in place. Take your time! It truly tested my patience putting the output and input shaft back together. If you are having difficulty check to see if any of the bearings popped out from the output shaft as you will see kept happening in the video, as well as walk away and take a break if you are having a really difficult time. Overall time with the transmission on the work bench I spent 7 hours doing the installation but with the added time of having cameras and making the videos for you guys. Also do not lose the retainer clips! There are three of them on the smallest shaft. They may pop out when you remove the shift fork so be ready.
Torque settings:
Case bolts are
NOTICE: Make sure that new bolts are installed.
Torque :
Stage 1: 18 Nm
Stage 2: 90 degree
Tq to stg one then tq 90 degrees past that moving the tq wrench in a circle make it 1/4 turn more of a turn after stage one tq is set.
Also the ring gear on the Diff is
Tighten each bolt 1 turn at a time.
Torque :
Stage 1: 50 Nm
Stage 2: 90 degree
[video=youtube_share;qsMLSALCnww]https://youtu.be/qsMLSALCnww[/video]
[video=youtube_share;2hjuQzYLeQw]https://youtu.be/2hjuQzYLeQw[/video]
[video=youtube_share;jOOhf6IufPg]https://youtu.be/jOOhf6IufPg[/video]
[video=youtube_share;haYV5lIKrGo]https://youtu.be/haYV5lIKrGo[/video]
[video=youtube_share;Zfpb7cFIZlo]https://youtu.be/Zfpb7cFIZlo[/video]
Interesting finds:
I found that the final drive ratio, even though it is sold by Pumaspeed or Sico Developments, are parts made from Ford UK. Another note is UK part numbers do not match USA part numbers and this made a little bit of confusion when trying to search for certain parts. Another point I would like to highlight was Rodmoe noted he did not have to change the shim for his Quaife Diff and I didn't have to do so either with my Wavetrac. This could either be a great coincidence or the LSD's are made so well into spec that there is no need for that step.
LSD Installation prep:
I opted to purchase the diff installation kit through Mountune that did not include the loctite. I purchased my loctite through amazon for a much less expensive rate. I bought 271 and 515 Loctite. Other things I purchased for taking the transmission apart was a new clutch slave cylinder through Tasca as well as new case bolts. Tools I purchased for this project was a bearing installation kit from Harbor freight, a micrometer, and a seal puller.
Final Drive Installation prep:
I would purchase the Mountune diff kit as you will be replacing the ring gear as well as the reverse gear shaft and the output shaft. When ordering the kit make sure to select the option for the main pinion bearing. This bearing you can not order in the USA as Ford does not make the part here state side. The other thing is make sure you get everything in your kit as when I ordered mine the main pinion bearing was missing. Although PumaSpeed quickly corrected this and the new bearing was at my front door in 3 days from the UK! Next you need 3 more bearings and a retainer bolt for the output shaft. I will list part numbers/links further below. I also highly suggest finding a transmission shop to replace and swap the gears once you have them removed from the transmission. The added cost for myself was $136 out the door to have a shop do this process. As simple as all these parts may seem now that it is laid out, no one knew which parts went to which shaft so I went through the process of ordering all the bearings and returning the incorrect ones.
Part numbers/links:
Mountune Diff Kit http://www.mountuneusa.com/ATB-Differential-Installation-Kit-Fiesta-ST-p/2364-atb-hw.htm
Loctite 271 thread locker
Loctite 515 Gasket maker
Clutch slave cylinder DG9Z-7A564-B
Case bolts W500311-S437
Pumaspeed final drive http://www.pumaspeed.com/product-Ford-Fiesta-ST-180-EcoBoost-431-Final-Drive_16814.jsp
or Sico Final drive https://www.sico-developments.co.uk...1-final-drive-replacement?variant=12732727812
Bearings for output shaft and reverse
AV6Z-7025-B
AV6Z-7025-A
DV6Z7065-A
Retainer Bolt AV6Z-7049-B
Installation notes:
Puller the axles seals out before removing the new old races or the differential bearings. There is a groove in the house to allow a flathead screwdriver or chisel to hammer on to remove the races. It helps to have a buddy work with you! I used a Vice to hold the ring gear in place as I torqued the new bolts to hold the new LSD in place. Take your time! It truly tested my patience putting the output and input shaft back together. If you are having difficulty check to see if any of the bearings popped out from the output shaft as you will see kept happening in the video, as well as walk away and take a break if you are having a really difficult time. Overall time with the transmission on the work bench I spent 7 hours doing the installation but with the added time of having cameras and making the videos for you guys. Also do not lose the retainer clips! There are three of them on the smallest shaft. They may pop out when you remove the shift fork so be ready.
Torque settings:
Case bolts are
NOTICE: Make sure that new bolts are installed.
Torque :
Stage 1: 18 Nm
Stage 2: 90 degree
Tq to stg one then tq 90 degrees past that moving the tq wrench in a circle make it 1/4 turn more of a turn after stage one tq is set.
Also the ring gear on the Diff is
Tighten each bolt 1 turn at a time.
Torque :
Stage 1: 50 Nm
Stage 2: 90 degree
[video=youtube_share;qsMLSALCnww]https://youtu.be/qsMLSALCnww[/video]
[video=youtube_share;2hjuQzYLeQw]https://youtu.be/2hjuQzYLeQw[/video]
[video=youtube_share;jOOhf6IufPg]https://youtu.be/jOOhf6IufPg[/video]
[video=youtube_share;haYV5lIKrGo]https://youtu.be/haYV5lIKrGo[/video]
[video=youtube_share;Zfpb7cFIZlo]https://youtu.be/Zfpb7cFIZlo[/video]
Last edited: