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Clank sound from underneath

Recently pulled the Boss out for the warmer weather. While cleaning the wheels I rolled the car forward slightly. To my surprise I heard a "clank" from underneath. :eek: My first thought was the two piece driveshaft. I continued to rock the car back and forth while in gear. Clank forward, clank backwards. The sound seems to be coming from the bell housing or input shaft or clutch maybe? More towards the front of the transmission. Any thoughts or advice? Anyone else notice/hear this before? I hope to visit the dealer soon but wanted to bounce this off you guys first! Thanks in advance!
 
ArizonaGT said:
Rearend gear backlash, most likely.

I thought that at first to but the sound if far forward of the rear end. I can hear the noise coming from the rear of the engine/front of the transmission. Seems totally different than rearend clunk too...more of a tinny sound. more clank than a clunk
 
Here is a short video of the sounds that I hear. After listening to the video it sounds like the springs in the clutch along with a clank or clunk just before you hear what sounds like a spring compressing. The video was taken just behind the belhousing, passenger side. BTW the car is in 1st gear. I am going to try to put the car in a different gear tonight to see if the sound changes.
What do you guys think?

http://youtu.be/VE4mh4PTGc8
 
ArizonaGT said:
OK, that does not sound normal.

I brought this up to my service guy last year (wasn't as prevelant then) and he, off the cuff, said "rear end slop, normal".

Anyone have any initial thoughts?
 
I have a drive line clunk in 6th gear when tipping back into the gas after coasting. My guess is the diff, either gears or a bushing. Took it to Galpin Ford and had their head service guy ride along so he could feel it. They drove 4 new Boss 302's and told me it's normal. The detroit locker in my 66 GT350 has less slop.
 

pufferfish

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Spring sound might be the sprung hub of the clutch disc. Might have some rust on the springs after sitting all winter.

The clunk is normal. Its all the gear backlash. There are 2 sets of gears that are engaged in the trans in all forward gears, then the axle gears. It's a lot of slop to take up and it will make noise as it is rocked back and forth.

Drive the car for a week and see if the spring noise goes away.
 
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the2finger said:
I have a drive line clunk in 6th gear when tipping back into the gas after coasting. My guess is the diff, either gears or a bushing. Took it to Galpin Ford and had their head service guy ride along so he could feel it. They drove 4 new Boss 302's and told me it's normal. The detroit locker in my 66 GT350 has less slop.

I have noticed the same in my car, in 5th and 6th at below 2000 rpm.
 
Finally made it in to the dealer. Ford dealer decided to put the car on the rack to pinpoint this clank sound better. From the tech "there is noticeably more slop than a new mustang and the spring sound is not normal". They have contacted the Ford tech hotline. Ford responded with the fact that parts are warrantable. Everything seems to be in line.... new clutch, right?

The dealership then brings out the Service manger (who btw wouldn't look me in the eyes). He started to ask if I drove the car to track event, or performed "drag racing" as well as questioned why I had brake ducts installed. This is when I become concerned about the dealers objectives. He then proceeds to remind me that if they remove the transmission and don't find anything, I am responsible for the repairs. I asked, “if you don’t feel that something is wrong, why do you have or want to inspect the sound further?” He proceeded to become agitated and responded with the same “you are responsible if we don’t find anything”. Btw, this dealer is a Roush dealer and act like they have never seen this drive train. Service manager also said my car with 9k “should sound different than a new like vehicle”. Any comments on proceeding? OH, I also asked if they would install and aftermarket instead of OEM clutch, while the transmission is removed. They refused and sated that the only clutch they would install if the OEM.

My question to the people that have had clutch replacement.... Was warranty covered/not covered established before work was performed? Is this truly on me until they find a failed part? Does anyone know of a good dealer around Iowa? Thanks for the help in advance!
 
Ford dealer didn't help me out when my clutch springs blew up...they told me the exact same line of crap. I even escalated to Ford customer service and they said the same thing. Granted...my clutch blew up at Watkins glen...and my racing seats...track tires, harnesses were all in so I couldn't deny it...but still...I thought it was awfully crappy that due to my track days and suspension mods only they told me to get lost for the clutch/spring assembly crackin.
 
kpetronis said:
Ford dealer didn't help me out when my clutch springs blew up...they told me the exact same line of crap. I even escalated to Ford customer service and they said the same thing. Granted...my clutch blew up at Watkins glen...and my racing seats...track tires, harnesses were all in so I couldn't deny it...but still...I thought it was awfully crappy that due to my track days and suspension mods only they told me to get lost for the clutch/spring assembly crackin.
I'm sorry that happened and there have been many BMO members that have had that same issue on track and the clutch was covered under warranty. Ford knows this is an issue and should replace it no matter what. I hope you didn't install a stock clutch again?
 
kpetronis said:
Ford dealer didn't help me out when my clutch springs blew up...they told me the exact same line of crap. I even escalated to Ford customer service and they said the same thing. Granted...my clutch blew up at Watkins glen...and my racing seats...track tires, harnesses were all in so I couldn't deny it...but still...I thought it was awfully crappy that due to my track days and suspension mods only they told me to get lost for the clutch/spring assembly crackin.

Do you have any pictures of what you assembly looked like, after the springs blew up?

Would anyone like to share pictures of clutch assembles that Ford has or hasn't covered under warranty?
 
NFSBOSS said:
I'm sorry that happened and there have been many BMO members that have had that same issue on track and the clutch was covered under warranty. Ford knows this is an issue and should replace it no matter what. I hope you didn't install a stock clutch again?

Nah I put an exedy clutch rated to 750+ HP in (and I have no intentions of super charging so that should be fine). I didn't have the moolah to go for McLeod or what have you. Put in the clutch, new lightweight flywheel, and slave cylinder.

No pics of the exploded clutch spring assembly, they didn't give me that part back.
 

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