Sounds From Tranny: (Shift) Thud, (Shift) Thud!
#1
Drifting
Thread Starter
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Hope everyone had a nice weekend.
Mine was good until everytime I shifted from 1st-2nd-3rd, and maybe even 4th to 5th, I heard a "thud" from the rear of the car when I moved the shifter to the next higher gear, before even letting the clutch out. It almost sounds like some is hitting the car with a rubber mallet.
The sound is loudest and most prominent shifting from 2nd to 3rd.
As far as I can tell, it doesn't happen during downshifts.
And there is some, but not much slack in the drivetrain.
Any ideas? How much does a used 951 tranny cost?
Thanks in advance.
sm
Mine was good until everytime I shifted from 1st-2nd-3rd, and maybe even 4th to 5th, I heard a "thud" from the rear of the car when I moved the shifter to the next higher gear, before even letting the clutch out. It almost sounds like some is hitting the car with a rubber mallet.
The sound is loudest and most prominent shifting from 2nd to 3rd.
As far as I can tell, it doesn't happen during downshifts.
And there is some, but not much slack in the drivetrain.
Any ideas? How much does a used 951 tranny cost?
Thanks in advance.
sm
#2
Burning Brakes
Join Date: Jul 2001
Location: Ams, NL
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SM
Not necessarily your tranny.
Might be play in the linking mechanism on the tranny.
There are some famous bolts up there.
Could even be the shifter handle / rod conn under the console.
TakeCare
Not necessarily your tranny.
Might be play in the linking mechanism on the tranny.
There are some famous bolts up there.
Could even be the shifter handle / rod conn under the console.
TakeCare
#3
Drifting
Thread Starter
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Hans,
Thanks for the reply. I've checked and readjusted the shifter and the bolts/e-clip in the console. Everything is fine up there.
The only reason I think it's the tranny is that the "thud" only happens after I've selected a gear. Not in between shifts (i.e. the rowing motion).
Also, the car shifts fine when it's not moving, motor on or off.
Any more ideas?
Thanks for the reply. I've checked and readjusted the shifter and the bolts/e-clip in the console. Everything is fine up there.
The only reason I think it's the tranny is that the "thud" only happens after I've selected a gear. Not in between shifts (i.e. the rowing motion).
Also, the car shifts fine when it's not moving, motor on or off.
Any more ideas?
#4
Burning Brakes
Join Date: Jul 2001
Location: Ams, NL
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SM
An kinda wild one:
The sound apears when the gears engage, just a fraction of a second after you shifted?
So when the clutch comes down?
Or just before?
When just before, it could also be low tranny oil level or wrong oil.
Specially an LSD can do funny things with low or wrong oil.
When while the clutch is coming down and power built-up starts than it could also be an clutch (disc spring?) problem in the very early stage.
I am just trying the simple solutions first.
Worst case will be synchro's or an bearing in the tranny on the way out.
Just for reference:
The slack in my drive train: both rear wheels off the ground (LSD) and in 1th gear is about 10 to 15 deg rotation on one wheel. No LSD will be a lot more.
TakeCare
EDIT>>>
Some second (or thirth) thoughts:
Only in up-shift:
What about CV joints (and the bolts), still tight?
Nut on rear wheel shaft still tight?
Rear wheel bearings?
Just trying to eliminate the simple ones first
TakeCare
An kinda wild one:
The sound apears when the gears engage, just a fraction of a second after you shifted?
So when the clutch comes down?
Or just before?
When just before, it could also be low tranny oil level or wrong oil.
Specially an LSD can do funny things with low or wrong oil.
When while the clutch is coming down and power built-up starts than it could also be an clutch (disc spring?) problem in the very early stage.
I am just trying the simple solutions first.
Worst case will be synchro's or an bearing in the tranny on the way out.
Just for reference:
The slack in my drive train: both rear wheels off the ground (LSD) and in 1th gear is about 10 to 15 deg rotation on one wheel. No LSD will be a lot more.
TakeCare
EDIT>>>
Some second (or thirth) thoughts:
Only in up-shift:
What about CV joints (and the bolts), still tight?
Nut on rear wheel shaft still tight?
Rear wheel bearings?
Just trying to eliminate the simple ones first
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
TakeCare
#5
Drifting
Thread Starter
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Hans,
The "thud" is there before I even let the clutch out after I shifted. So I push the clutch in, shift gears, and the sound occurs while the clutch pedal is still pushed in, not released.
When I let the clutch pedal out and start to apply power, I don't hear any noise, I don't think.
As for the clutch causing this, it could be. I believe it's the rubber center type the PO put in. When I start the car up in the morning, I hear a "grinding" noise from the clutch which some say is the release bearing on the way out. Do you think this is related?
The "thud" is there before I even let the clutch out after I shifted. So I push the clutch in, shift gears, and the sound occurs while the clutch pedal is still pushed in, not released.
When I let the clutch pedal out and start to apply power, I don't hear any noise, I don't think.
As for the clutch causing this, it could be. I believe it's the rubber center type the PO put in. When I start the car up in the morning, I hear a "grinding" noise from the clutch which some say is the release bearing on the way out. Do you think this is related?
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