Manual Transmission's Thud or Clunk Sound - More Refined But Still Plenty Fun

Edmunds.comEdmunds.com Member, Administrator, Moderator Posts: 10,137
edited March 2015 in Ford
imageManual Transmission's Thud or Clunk Sound - More Refined But Still Plenty Fun

The manual transmission in our 2015 Ford Mustang GT makes a thud or clunk sound when upshifting.

Read the full story here


Comments

  • stuntman_mikestuntman_mike Member Posts: 57
    Even Ford Racing now offers the Tremec T-56 Magnum XL transmission (P/N M-7003-M6XL). I know it would be too good to be true; but I'd rather pay a couple thousand dollars more to be able to option the Tremec when I ordered the car as opposed to tossing out that Chinese-made Getrag and having to buy the Tremec once I took delivery.
  • banhughbanhugh Member Posts: 315
    edited March 2015
    Oh the joys of first year production cars was my first thought. But you say it's been an issue with past generations. It must be part of the heritage!
  • s197gts197gt Member Posts: 486
    edited March 2015
    pretty sure what you are describing is normal. my wife and her friend went on a road (shopping) trip once and she said, "what is that clunking noise?" every time i shifted. i said, "that's a mustang."

    also, i just watched motorweek's review of the '15 mustang gt and they said something to the affect that the mustang, while much more quiet, still had a little transmission thunk to remind you it's a mustang. i'm paraphrasing...

    my clunk comes from the rear, i don't think you said where your sound was coming from but if it is toward the rear i would definitely think it is normal. a "standard feature" if you will...

    here you go... fast forwarded to relevant comments:

  • glossgloss Member Posts: 150
    My Fiesta ST exhibits the same behavior.
  • nsx603nsx603 Member Posts: 5
    My Focus ST with a Getrag box does the exact same thud, I theorize it is the soft gearbox + engine mounts letting a lot of slack get in the way. With harder mounts, the issue would go away but the car would buzz too much inside.
  • mcesareymcesarey Member Posts: 11
    This thud while upshifting is most likely a result of a weak bracket under the car that the shifter mounts to. Ford uses a mushy bracket to help isolate vibration, but it allows the shifter to move around slightly while accelerating, which causes the linkage to be just a little off. An aftermarket bracket is solid, so everything is held in place even under full throttle so you don't get that annoying clunk while upshifting. I dealt with this in my 2013 GT/CS, it got to where I didn't even enjoy driving the car.
  • thecardoc3thecardoc3 Member Posts: 5,463
    edited March 2015
    Some things have to be felt first hand and investigated to try to really be sure. As I read this especially the part where the "clunk" can be made to happen when stopped and then shifting from neutral to first the biggest thing that is changing is the rotational speed of the countershaft in the transmission and the gears in mesh with it that are freewheeling. They all have to stop moving for you to get the transmission into first gear. That can be a significant amount of inertia that has to be dealt with when shifting the gears. Now add a little backlash somewhere and you could easily have a sound or sensation that you might be able to notice but would have no impact on the transmission's lifespan.
  • mattpedersenmattpedersen Member Posts: 2
    I have the exact issue in my 2008 Honda Accord EX-L 5MT. So it's not just a Ford issue.
  • corengocorengo Member Posts: 2
    I have the same issue on my 2015 GT with performance pkg but it only happens at low rpms like if i shift normally around 2k - 2.5k rpm. At high rpm it doesnt happen. Oh and 3rd gear sometimes is a little more noisy and tricky than the other gears to shift. Downshifting never happens, only upshifting.
  • evilanjevilanj CaliforniaMember Posts: 2
    I have a 2015 Mustang GT Premium PP and mine also has the clunk in rear end. It does it intermittently when going from neutral t first, but almost always when going from 1-2 and 2-3. I have an appointment tomorrow to have it looked at. I have already had one guy from dealership test drive it and he most definitely heard the clunk. It also sounds like the linkage or something is loose as it makes quite a racket when you are coming to a stop and engage the clutch. Sounds very sloppy and loud. It's embarassing when you pull up next to someone and they too can hear it. I know this isn't normal and I now have 9,000 miles on it and it has been making this sound since the day we bought it. We even test drove another Mustang like ours to see if it made the same noise and, of course, it didn't.

    If they solve this problem tomorrow, I will definitely share it with everyone on here.
  • evilanjevilanj CaliforniaMember Posts: 2
    I have now taken my Mustang in three different times to try and get this horrid clunk in the rear ended fixed. Although the mechanics can clearly hear the noise whilst inside the vehicle, they are claiming they cannot hear it on the outside when it's up on the lift. They have already replaced the driveshaft and checked the backlash in the differential. Can't seem to pull their heads out and realize that regardless of where the hell this CLUNK is coming from, it's not right!! So next I guess we start the buy back process. I didn't want to buy a Ford in the first place, and this just confirmed it. LAME!? We are going to try one more time while I'm in California to get this resolved. If not, they can take it and shove it!! 


  • dan_wilsondan_wilson Member Posts: 1
    I noticed the clunk during my test drive of the 2016 GT PP and also on the 2016 GT PP I ended up buying (2 different cars)
Sign In or Register to comment.