Focus St mk4 clunking Elsd,transmission

[fugleman]

Has anyone with the automatic 7speed on their Focus ST mk4/mk4.5 noticed a clunking/knocking from the transmission/Elsd when on and off light throttle (2nd or 3rd gear 20km to 50 km approx) -as if in bumper to bumper traffic on off throttle or approaching a round about coasting off throttle then on throttle again-sounds Just like a worn cv or excessive backlash in a diff.? It only occurs when the transmission/Elsd fluid is warmed up, when cold perfect.

Ford replaced the whole transmission with a new one last week(stating it was fixed) but it still clunks the same when warmed up. So i am suspecting it's the Elsd but before hounding Ford again thought i'd ask the forum.

>Have heard the borg warner FXD lsd can have noisy (chatter)clutch packs but that's when slow turning on tight corners, this is always.

Also do the Elsd run like an open diff(disengage) when off throttle and close/lockup(re engage say 10%- 100% as required) when back on throttle as they can adjust every 150ms??

thanks

[stefcio007]

Didn't know they came in 7 speed? Mine's an 8 speed torque converter. The issue you are describing sounds like what I had with my MK3 6 speed DCT that sounded like someone punching a paper bag when lifting off the throttle.

[fugleman]

Yes the 7F40 is basically an 8F35 (8 speed) with the 3rd gear mapped out with a bit beefier torque handling.
The original trans and now the new replaced trans were fine-smooth shifting quiet etc. so still points to the Elsd clunking when fluid warmed up going from load to no load? Car in for another look with dealer on 15th November so we'll see!

[stefcio007]

Whoops, just noticed you mentioned ST.
Makes sense now.

You should check out the group on Facebook “Mk4 Focus ST Owners Australia”, very active.
If you don’t have Facebook I can post a link to this post and write the replies here.

[fugleman]

thanks for the link, just requested to join

[John Humpo]

Originally Posted by fugleman

thanks for the link, just requested to join

Hi I have a 2021MY Focus ST 7 speed auto when i drive in normal mode it is smooth shifting at all times but when i'm in Sport/Track mode i do notice the shifts are harsher/quicker which is what you would expect, but it doesn't sound like an ELSD issue just more sudden & quicker shifts, hope you sort the issue out soon.

[fugleman]

Yes John mine is smooth shifting in normal and a bit more abrupt on sport or track also when on throttle driving but the problem is when off throttle (coasting) then foot back on throttle slightly- i get that backlash clunk.
Going back to ford next week to take technician out to let them feel it-again! as it's pretty bad now summer heat is here.

[John Humpo]

Yes i get what your saying, getting a technician to go with you is a good move to experience the issue first hand let us know how you get on, best of luck.