Clunking from rear info (NOT the LSD clutch pack issue)
05-21-2008, 09:06 PM
#41
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I too am having the same clunking and rattling issue. I have a 2005 Auto Z51 with 26k . The last time I had this problem was at 23k miles ago. I currently have it at the Dealership and They have ordered a new clutch pack for it. I will pass on any other info I get from the Dealer.
05-21-2008, 11:15 PM
#42
Melting Slicks
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I too am having the same clunking and rattling issue. I have a 2005 Auto Z51 with 26k . The last time I had this problem was at 23k miles ago. I currently have it at the Dealership and They have ordered a new clutch pack for it. I will pass on any other info I get from the Dealer.
07-03-2008, 06:41 PM
#43
Melting Slicks
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Heads Up- FYI:
Reviving this thread again to suggest a possible fix to this rear end clunk as a result of what I have labeled a troubled transimmision shift. The following TSB was brought to my attention and described under the keywords; Bump delay second slip third - dated April 17th 2008. Subject: Flare or Hard 2-3 shifts.
Particularly this can be referenced under:
Document ID 2101618
Service Bulletin 4052
NHTSA item # 10022794
It's my conntention that becuase of the described delayed shift, some vettes experience a clunk as a result of being initiatlly stuck in gear due to this delayed shift condition. This is not related to the Clunk & Chatter TSB as commonly prescribed and duely noted. Particularly the clunk can only ocur (intermittently) based on the transmision temperature either primarily below 40 degree C (104 degree F), but can alo be present at almost any trans temp. Though harsh Shifts are more likely to occur at less than 50% tp - per TSB.
The Fix: I'm not particularly thrilled about this, but is too replace the clutch fluid seal rings caused by leaking. This is specific to the 3-5-R Clutch fluid seal ring (230).
I will pursue this and will report back as to a potential fix.
Reviving this thread again to suggest a possible fix to this rear end clunk as a result of what I have labeled a troubled transimmision shift. The following TSB was brought to my attention and described under the keywords; Bump delay second slip third - dated April 17th 2008. Subject: Flare or Hard 2-3 shifts.
Particularly this can be referenced under:
Document ID 2101618
Service Bulletin 4052
NHTSA item # 10022794
It's my conntention that becuase of the described delayed shift, some vettes experience a clunk as a result of being initiatlly stuck in gear due to this delayed shift condition. This is not related to the Clunk & Chatter TSB as commonly prescribed and duely noted. Particularly the clunk can only ocur (intermittently) based on the transmision temperature either primarily below 40 degree C (104 degree F), but can alo be present at almost any trans temp. Though harsh Shifts are more likely to occur at less than 50% tp - per TSB.
The Fix: I'm not particularly thrilled about this, but is too replace the clutch fluid seal rings caused by leaking. This is specific to the 3-5-R Clutch fluid seal ring (230).
I will pursue this and will report back as to a potential fix.
08-15-2008, 07:57 PM
#44
Burning Brakes
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Problem FIXED!
A few months ago I took mine in for the rear end chatter. The noise went away.
Then a hollow ticking/ cracking sound kept coming and getting worse through out the months. I finally took in back in and they said GM has a bulletin out for it. They replaced a few nuts or bolts on the rear end so that noise is GONE.
A few months ago I took mine in for the rear end chatter. The noise went away.
Then a hollow ticking/ cracking sound kept coming and getting worse through out the months. I finally took in back in and they said GM has a bulletin out for it. They replaced a few nuts or bolts on the rear end so that noise is GONE.
08-15-2008, 10:12 PM
#45
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Problem FIXED!
A few months ago I took mine in for the rear end chatter. The noise went away.
Then a hollow ticking/ cracking sound kept coming and getting worse through out the months. I finally took in back in and they said GM has a bulletin out for it. They replaced a few nuts or bolts on the rear end so that noise is GONE.
A few months ago I took mine in for the rear end chatter. The noise went away.
Then a hollow ticking/ cracking sound kept coming and getting worse through out the months. I finally took in back in and they said GM has a bulletin out for it. They replaced a few nuts or bolts on the rear end so that noise is GONE.
Did you get a repair bill/sheet that listed more info than above?
Last edited by Xlr8yourC5; 08-15-2008 at 10:14 PM.
08-25-2008, 04:11 PM
#46
Melting Slicks
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Updating an Old thread:
In re: I had the TSB performed as I described above in post #44:
Update:
After the regional engineer came out I too had the PIP4395_Flare or Harsh Shifts 2-3, Bump Delay TSB performed re: post #27.
Result: A significant difference in the shifting characeristics of the vert. Shifts were noticably faster and it appears to have resolved the rear end clunk accompanied with it. Though more time is needed to assure the repair is persitent, as I did notice a muffled bump at low speeds initially after the repair [ none since], it was nonetheless more like a slow gear change than a hard missed [delayed] shift clunk. Perhaps requesting a download or update on the transmission shifts might be in order as a last step. Anyway to anyone who feels they have this issue it is adviseable to do this service or at least speak with a service technician about it. I know scary in re: transmission.
Here is an excellent description and clarification of the condition/concern that I experienced along with a hard rear differential clunk:
Coast Down [Hard Differential] Clunk:
An example of this is you are driving in town in heavy traffic approaching a red light or making a turn. You’re going 20 mph [+/- 10 mph] and have let up on the throttle for several seconds coasting. As you get close to the light it turns green you step on the throttle to accelerate back up to speed. The car seems to hesitate or search for the right gear, and then shortly there afterwards you experience a hard clunk/bump from the rear. Notably the transmission acts like it’s in-between gears and cant decide which one it wants to go into for a second or two and then hard shifts/clunks into place. It does not occur every coast down. It must require that certain indeterminate factors be met? Maybe speed, length of coast, gear you were in, etc. It really interferes/modifies your driving.
This hesitation makes you loss confidence in the car, in getting out of the way in quickly responding to a situation.
Special Thanks to wbear for help in describing this situtation.
Hope this helps some...
In re: I had the TSB performed as I described above in post #44:
Update:
After the regional engineer came out I too had the PIP4395_Flare or Harsh Shifts 2-3, Bump Delay TSB performed re: post #27.
Result: A significant difference in the shifting characeristics of the vert. Shifts were noticably faster and it appears to have resolved the rear end clunk accompanied with it. Though more time is needed to assure the repair is persitent, as I did notice a muffled bump at low speeds initially after the repair [ none since], it was nonetheless more like a slow gear change than a hard missed [delayed] shift clunk. Perhaps requesting a download or update on the transmission shifts might be in order as a last step. Anyway to anyone who feels they have this issue it is adviseable to do this service or at least speak with a service technician about it. I know scary in re: transmission.
Here is an excellent description and clarification of the condition/concern that I experienced along with a hard rear differential clunk:
Coast Down [Hard Differential] Clunk:
An example of this is you are driving in town in heavy traffic approaching a red light or making a turn. You’re going 20 mph [+/- 10 mph] and have let up on the throttle for several seconds coasting. As you get close to the light it turns green you step on the throttle to accelerate back up to speed. The car seems to hesitate or search for the right gear, and then shortly there afterwards you experience a hard clunk/bump from the rear. Notably the transmission acts like it’s in-between gears and cant decide which one it wants to go into for a second or two and then hard shifts/clunks into place. It does not occur every coast down. It must require that certain indeterminate factors be met? Maybe speed, length of coast, gear you were in, etc. It really interferes/modifies your driving.
This hesitation makes you loss confidence in the car, in getting out of the way in quickly responding to a situation.
Special Thanks to wbear for help in describing this situtation.
Hope this helps some...
Last edited by User 2623; 08-25-2008 at 04:20 PM.
09-17-2008, 04:37 PM
#47
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2nd time around will it work this time?
I'm no mechanic I just drive the car so forgive me for any ignorance now and in the future.
My 2007 Automatic was serviced back in 2007 after just 5000 miles for this Clutch Pack Replacement/Chattering problem. Now at 19000 a few months later its in for service again with the same problem. I'm irritated to say the least!!! Ok maybe this is common, maybe this is the standard, but its infuriating to a non mechanical person like me who buys a $60K car expecting it to be a good car but has the same problem twice before reaching 20000 miles. Im sure it will need repaired again just as the warranty runs out. I called today and my warranty runs out at 36K ...is that right for this issue? I thought this would be considered the drive train. I know I dont have the new fancy 100K warranty but isnt the drive train warranty more than 36K? Anyway thats another issue. Lets not digress. This Chattering issues seems to date back pretty far for Corvette. Maybe its time for a class action GM buy back suite with about 50000 unsatisfied customers.
Ok Im done...I love Corvettes. I owned a 2000 for 6 years and now my 2007. I just missed the employee pricing and the new 100K warranty by one year.
My 2007 Automatic was serviced back in 2007 after just 5000 miles for this Clutch Pack Replacement/Chattering problem. Now at 19000 a few months later its in for service again with the same problem. I'm irritated to say the least!!! Ok maybe this is common, maybe this is the standard, but its infuriating to a non mechanical person like me who buys a $60K car expecting it to be a good car but has the same problem twice before reaching 20000 miles. Im sure it will need repaired again just as the warranty runs out. I called today and my warranty runs out at 36K ...is that right for this issue? I thought this would be considered the drive train. I know I dont have the new fancy 100K warranty but isnt the drive train warranty more than 36K? Anyway thats another issue. Lets not digress. This Chattering issues seems to date back pretty far for Corvette. Maybe its time for a class action GM buy back suite with about 50000 unsatisfied customers.
Ok Im done...I love Corvettes. I owned a 2000 for 6 years and now my 2007. I just missed the employee pricing and the new 100K warranty by one year.
05-11-2009, 11:51 AM
#48
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I have a similar issue on my 07
I just bought an 07 coupe with z51 and 6sp manual, 16k miles.
I get a hollow cluncking noise coming from the rear when starting to reverse or starting to go forward. Low speed only < 10mph.
I get a little of the same when going slow in first gear and getting on and off the throttle mildly - what they call parade driving. I also get a little sometimes when approaching a light and I put the clutch in.
It is completely normal if I get over 20 mph.
I get no noises at all when going around corners.
I read this forum and decided to check the axle nut issue. I had it. I got it fixed under warranty. Problem got noticably better not 100%. Same type of noise though.
Being my first corvette I don't know how much of this is normal. I know there is a TBS that says some of it is normal for this car but it seems to me to be a little too much.
I got underneath and there does not seem to be anything loose except for maybe the rear calipers floating and the front wheels have a slight side to side clunck. I think this is just the steering rack play, maybe, not sure of this either.
Can anybody describe how much of this is normal?
One a side note, I also get the slight synronizer vibration when shifting when the tranny oil is cold. Normal, although a little notchy, when warmed up.
I get a hollow cluncking noise coming from the rear when starting to reverse or starting to go forward. Low speed only < 10mph.
I get a little of the same when going slow in first gear and getting on and off the throttle mildly - what they call parade driving. I also get a little sometimes when approaching a light and I put the clutch in.
It is completely normal if I get over 20 mph.
I get no noises at all when going around corners.
I read this forum and decided to check the axle nut issue. I had it. I got it fixed under warranty. Problem got noticably better not 100%. Same type of noise though.
Being my first corvette I don't know how much of this is normal. I know there is a TBS that says some of it is normal for this car but it seems to me to be a little too much.
I got underneath and there does not seem to be anything loose except for maybe the rear calipers floating and the front wheels have a slight side to side clunck. I think this is just the steering rack play, maybe, not sure of this either.
Can anybody describe how much of this is normal?
One a side note, I also get the slight synronizer vibration when shifting when the tranny oil is cold. Normal, although a little notchy, when warmed up.
05-11-2009, 01:46 PM
#49
Unfortuantely there seems to be quite a bit of audible lash in the vette driveline. The dealership didn't do anything about it for me, I think it's just something we have to live with. Not quite acceptable IMO. You can hear the clunk if you raise the rear up and turn a wheel back and forth by hand. I think most of my noise is coming from inside the tranny itself, so not worth even trying to fix it.
I have an 08 6sp with 40k and the tranny's always shifted totally smooth when warmed up. My synchros are a bit different from yours though. Shoulda got an 08 :P You could try changing the tranny oil. I've had good luck with Redline smoothing out synchro action on my previous cars, but the GM fill's been working fine in this car.
You should track down the front wheel clunk, that doesn't seem normal.
Another thing that goes bad within 15-30k in my experience are swaybar endlinks. I'm on my third set of fronts and second rears. You can hear these knocking when driving at slow speed down a bumpy alley or something.
It's not a perfect car, but close enough :P I'm sure that's what the GM engineers say to themselves when they go home from work every day
I have an 08 6sp with 40k and the tranny's always shifted totally smooth when warmed up. My synchros are a bit different from yours though. Shoulda got an 08 :P You could try changing the tranny oil. I've had good luck with Redline smoothing out synchro action on my previous cars, but the GM fill's been working fine in this car.
You should track down the front wheel clunk, that doesn't seem normal.
Another thing that goes bad within 15-30k in my experience are swaybar endlinks. I'm on my third set of fronts and second rears. You can hear these knocking when driving at slow speed down a bumpy alley or something.
It's not a perfect car, but close enough :P I'm sure that's what the GM engineers say to themselves when they go home from work every day
Last edited by steel_3d; 05-12-2009 at 02:25 PM.
05-11-2009, 03:57 PM
#50
Burning Brakes
Mine makes a few different noises now.
When I get time I'll take it in, but my 08 A6 with 12k miles makes one noise turning at slow speed, kind of a scraping sound, and also has a nice clunk when off and then on the gas at slow speeds. Haven not had any other reasons for warranty work yet, but this has to be fixed.
Can't wait to get the loaner Aveo...
Can't wait to get the loaner Aveo...
05-11-2009, 08:08 PM
#51
Melting Slicks
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You guys need to at least check the sway bar end links. they wear out quickly. and are an easy fix.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
05-12-2009, 06:48 AM
#52
Burning Brakes
You guys need to at least check the sway bar end links. they wear out quickly. and are an easy fix.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
05-14-2009, 11:04 AM
#53
Safety Car
You guys need to at least check the sway bar end links. they wear out quickly. and are an easy fix.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
they dont even have a real "race" and pivot ball arrangement. I can reach up under my car and yank on my rear right link and it clunks.
Before that I tightened every bolt on the front and back until it dawned on me what was making the noise.
05-20-2009, 10:21 AM
#54
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Sway bar links hah? 17K miles hah? Good tip. I will look at this again.
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
05-20-2009, 12:37 PM
#55
Sway bar links hah? 17K miles hah? Good tip. I will look at this again.
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
05-20-2009, 01:05 PM
#56
Sway bar links hah? 17K miles hah? Good tip. I will look at this again.
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
I bought the car with 16K and it has close to 17K now. To my knowledge they have never been changed.
I thought of this and several other things but everything seems tight.
What is the 'best' procedure for checking the sway bar links?
I tried to move them around with my hand while weight is on the car, while jacked up on one side, etc.
In other works, should I have the car on the ground or jacked up?
If jacked up I assume it will have to be jacked up evenly on both sides or else there will be pressure on them making them appear tight.
I will try moving the car back and forth from the door too.
Do the front ones go easy too?
I believe that there is a similar noise coming from the right front too.
These noises are a 'hollow clunk' at very low speed only. Above 15 mph it is perfect.
Does this sound like stabilizer links?
Thanks
06-08-2009, 09:57 AM
#57
4th Gear
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Update on my hollow clunking noises
Well, I have good news.
After replacing one stay bar link and two service bulletins the car is just like new.
Here is a total of what was done to fix all problems.
1. Service bulletin to replace rear axle nuts, loctite and torque (TSB 07-04-95-001A)
2. Replace right front sway bar link.
3. Service bulletin to replace differential fluid (TBS 07-04-20-002A)
All clunks are gone, all noises are now quite, it rides like a million bucks now.
Thanks for all your help.
After replacing one stay bar link and two service bulletins the car is just like new.
Here is a total of what was done to fix all problems.
1. Service bulletin to replace rear axle nuts, loctite and torque (TSB 07-04-95-001A)
2. Replace right front sway bar link.
3. Service bulletin to replace differential fluid (TBS 07-04-20-002A)
All clunks are gone, all noises are now quite, it rides like a million bucks now.
Thanks for all your help.
03-20-2017, 04:44 PM
#58
Drifting
Member Since: Dec 2015
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I am wondering if you had this taken care of yet. The clunk can be the wheel driveshaft nuts. The original nuts not holding their torque, allowing the play causing the clunk at low speeds (and yes, when turning also).
There is also a bulletin from GM regarding a "snap clunk noise" when turning that can be associated with the stabilizer links:
"Condition/Concern:
Some customers may comment of a snap clunk noise from under the vehicle. This may occur while driving or parking lot maneuvers. This may be the result of the stabilizer links making noise.
Recommendation/Instructions:
Isolate the front and rear stabilizer bar links one at a time and evaluate. Replace any link subject to noise.
Note: The XLR base vehicle is equipped with a front stabilizer only. XLR V-series and the Chevrolet Corvette have front and rear stabilizers.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed."
The wheel driveshaft nut bulletin: ##07-04-95-001: Tapping or Scraping Noise From Rear Wheel Area (Replace Wheel Drive Shaft Nut)
I know it says tapping or scaping, but this TSB has also cured the problem as well.
Best of luck
There is also a bulletin from GM regarding a "snap clunk noise" when turning that can be associated with the stabilizer links:
"Condition/Concern:
Some customers may comment of a snap clunk noise from under the vehicle. This may occur while driving or parking lot maneuvers. This may be the result of the stabilizer links making noise.
Recommendation/Instructions:
Isolate the front and rear stabilizer bar links one at a time and evaluate. Replace any link subject to noise.
Note: The XLR base vehicle is equipped with a front stabilizer only. XLR V-series and the Chevrolet Corvette have front and rear stabilizers.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed."
The wheel driveshaft nut bulletin: ##07-04-95-001: Tapping or Scraping Noise From Rear Wheel Area (Replace Wheel Drive Shaft Nut)
I know it says tapping or scaping, but this TSB has also cured the problem as well.
Best of luck
03-20-2017, 10:13 PM
#59
Racer
mine had all four endlinks trashed... upgraded to a better part...but it did have the gear lash problem... the diff case broke ..so i got another diff..it had 105k on it...the gear lash was disgusting..clanging..and jerking..it fwas total ****...so i took the side plates with the ring gear and pinion from the original diff that had 60kon them and installed into the 06 diff case... and the problem is 95 percent gone...
it still has some lash in it..but thats the way it goes with metal on metal parts...ring and pinions are a wear and tear item..even more so with performance engines twisting them...
metal on metal...something has to give
it still has some lash in it..but thats the way it goes with metal on metal parts...ring and pinions are a wear and tear item..even more so with performance engines twisting them...
metal on metal...something has to give
04-25-2018, 11:15 AM
#60
Burning Brakes
Updating an Old thread:
In re: I had the TSB performed as I described above in post #44:
Update:
After the regional engineer came out I too had the PIP4395_Flare or Harsh Shifts 2-3, Bump Delay TSB performed re: post #27.
Result: A significant difference in the shifting characeristics of the vert. Shifts were noticably faster and it appears to have resolved the rear end clunk accompanied with it. Though more time is needed to assure the repair is persitent, as I did notice a muffled bump at low speeds initially after the repair [ none since], it was nonetheless more like a slow gear change than a hard missed [delayed] shift clunk. Perhaps requesting a download or update on the transmission shifts might be in order as a last step. Anyway to anyone who feels they have this issue it is adviseable to do this service or at least speak with a service technician about it. I know scary in re: transmission.
Here is an excellent description and clarification of the condition/concern that I experienced along with a hard rear differential clunk:
Coast Down [Hard Differential] Clunk:
An example of this is you are driving in town in heavy traffic approaching a red light or making a turn. You’re going 20 mph [+/- 10 mph] and have let up on the throttle for several seconds coasting. As you get close to the light it turns green you step on the throttle to accelerate back up to speed. The car seems to hesitate or search for the right gear, and then shortly there afterwards you experience a hard clunk/bump from the rear. Notably the transmission acts like it’s in-between gears and cant decide which one it wants to go into for a second or two and then hard shifts/clunks into place. It does not occur every coast down. It must require that certain indeterminate factors be met? Maybe speed, length of coast, gear you were in, etc. It really interferes/modifies your driving.
This hesitation makes you loss confidence in the car, in getting out of the way in quickly responding to a situation.
Special Thanks to wbear for help in describing this situtation.
Hope this helps some...
In re: I had the TSB performed as I described above in post #44:
Update:
After the regional engineer came out I too had the PIP4395_Flare or Harsh Shifts 2-3, Bump Delay TSB performed re: post #27.
Result: A significant difference in the shifting characeristics of the vert. Shifts were noticably faster and it appears to have resolved the rear end clunk accompanied with it. Though more time is needed to assure the repair is persitent, as I did notice a muffled bump at low speeds initially after the repair [ none since], it was nonetheless more like a slow gear change than a hard missed [delayed] shift clunk. Perhaps requesting a download or update on the transmission shifts might be in order as a last step. Anyway to anyone who feels they have this issue it is adviseable to do this service or at least speak with a service technician about it. I know scary in re: transmission.
Here is an excellent description and clarification of the condition/concern that I experienced along with a hard rear differential clunk:
Coast Down [Hard Differential] Clunk:
An example of this is you are driving in town in heavy traffic approaching a red light or making a turn. You’re going 20 mph [+/- 10 mph] and have let up on the throttle for several seconds coasting. As you get close to the light it turns green you step on the throttle to accelerate back up to speed. The car seems to hesitate or search for the right gear, and then shortly there afterwards you experience a hard clunk/bump from the rear. Notably the transmission acts like it’s in-between gears and cant decide which one it wants to go into for a second or two and then hard shifts/clunks into place. It does not occur every coast down. It must require that certain indeterminate factors be met? Maybe speed, length of coast, gear you were in, etc. It really interferes/modifies your driving.
This hesitation makes you loss confidence in the car, in getting out of the way in quickly responding to a situation.
Special Thanks to wbear for help in describing this situtation.
Hope this helps some...
