HELP! I think....?
02-10-2003, 12:00 AM
#1
Addict
Rennlist Member
Rennlist Member
Thread Starter
HELP! I think....?
Hello
After a brilliant track event a few weeks ago, I noticed a cluncking sound when changing gears on my 91 Turbo...
I took the car into Porsche, who claimed they could not replicate the problem. I was in Shanghai, and therefore had to wait until late last week to pick the car up. When I picked it up, I too could not replicate the sound
However, I managed to get the car up on a hoist (one of those that lift the car and leave the wheels free). Here's what I did, and what we discovered....
- when rotating the rear wheels one at a time, the cluncking is prominent, and if one listens carefully it sounds like it is right near, or just behind the gearbox.
- the wheels have a small bit of 'play' in opposite directions (ie I can turn one wheel one way and the other the other way), and when doing so the sound is worst.
- if I turn both wheels in the same direction simultaneously, the sound is there, but not nearly as bad.
Any ideas? Should I quickly go hide my wallet before Porsche see it?
Do I start to break out into a cold sweat? <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />
Thanks in advance!!
After a brilliant track event a few weeks ago, I noticed a cluncking sound when changing gears on my 91 Turbo...
I took the car into Porsche, who claimed they could not replicate the problem. I was in Shanghai, and therefore had to wait until late last week to pick the car up. When I picked it up, I too could not replicate the sound
However, I managed to get the car up on a hoist (one of those that lift the car and leave the wheels free). Here's what I did, and what we discovered....
- when rotating the rear wheels one at a time, the cluncking is prominent, and if one listens carefully it sounds like it is right near, or just behind the gearbox.
- the wheels have a small bit of 'play' in opposite directions (ie I can turn one wheel one way and the other the other way), and when doing so the sound is worst.
- if I turn both wheels in the same direction simultaneously, the sound is there, but not nearly as bad.
Any ideas? Should I quickly go hide my wallet before Porsche see it?
Do I start to break out into a cold sweat? <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" /> Thanks in advance!!
02-10-2003, 12:34 AM
#2
Rennlist Member
Probably the blind leading the blind here, but I like to grasp at straws when my wallet is about to hoovered. It's a very long shot, but the noise could be your LSD. Others have complained about a a noise in certain manoeuvers, albeit most of them seem to be made when reversing and turning at the same time.
Hope it's nothing too serious.
Hope it's nothing too serious.
02-10-2003, 03:15 AM
#3
Addict
Rennlist Member
Rennlist Member
Thread Starter
Hi John!! <img border="0" alt="[bigbye]" title="" src="graemlins/xyxwave.gif" />
How many sleeps has it been with your baby
Are you back in Vanuatu yet, or are you permanently back in NZ?
As far as the clunking goes... I was wondering if it was the... (ok, here comes one of my long-winded, completely non-technical explanations of a part I know exists but have no idea what the tech-talk word is....) - that thingy (or four I think) that act as guiding cogs - the ones spaced around, and which 'walk' around the main cog... <img border="0" alt="[ouch]" title="" src="graemlins/c.gif" />
Are they called spider - somethings?
Anyhoooo -
- them? Wondered if there was play in them since the sound is worse when I try to turn the wheels in opposite directions, but less when I spin the wheels in the same direction simultaneously...
Man - I gotta learn the tech-speak... this is rediculous <img border="0" alt="[oops]" title="" src="graemlins/oops.gif" />
Any ideas anyone?
How many sleeps has it been with your baby
Are you back in Vanuatu yet, or are you permanently back in NZ?
As far as the clunking goes... I was wondering if it was the... (ok, here comes one of my long-winded, completely non-technical explanations of a part I know exists but have no idea what the tech-talk word is....) - that thingy (or four I think) that act as guiding cogs - the ones spaced around, and which 'walk' around the main cog... <img border="0" alt="[ouch]" title="" src="graemlins/c.gif" />
Are they called spider - somethings?
Anyhoooo -
- them? Wondered if there was play in them since the sound is worse when I try to turn the wheels in opposite directions, but less when I spin the wheels in the same direction simultaneously...Man - I gotta learn the tech-speak... this is rediculous <img border="0" alt="[oops]" title="" src="graemlins/oops.gif" />
Any ideas anyone?
02-10-2003, 02:09 PM
#4
Rennlist Member
Hi Kevin,
I'm settled back in NZ for good now, hallelujah.
So far 87 sleeps have passed since I've been reunited with my baby. I've encountered a few of its brothers and sisters in that time. I went on a local Porsche Club run and met a man with a Speed Yellow 3.6, he said there are 8 Turbo 3.6's in NZ. So far I've seen 3 midnight blue ones and his. I know there's a Guards Red X88 out there, but have no idea what colour the other two are. It sure was fun following the Speed Yellow one, I drive mine all the time so I don't get to see it in action.
I'm settled back in NZ for good now, hallelujah.
So far 87 sleeps have passed since I've been reunited with my baby. I've encountered a few of its brothers and sisters in that time. I went on a local Porsche Club run and met a man with a Speed Yellow 3.6, he said there are 8 Turbo 3.6's in NZ. So far I've seen 3 midnight blue ones and his. I know there's a Guards Red X88 out there, but have no idea what colour the other two are. It sure was fun following the Speed Yellow one, I drive mine all the time so I don't get to see it in action.
02-10-2003, 03:05 PM
#5
Drifting
You may want to start with the simple things first:
1. Change your transmission oil to Swepco. Your track event might have overheated the fluid in there and you might not have the right viscosity anymore.
2. Check to ensure your clutch is operating correctly. Your dual mass flywheel might be broken. I think this was common enough that Porsche did a recall early in the car's life to update the part. My car had an updated flywheel when I bought it.
3. Ensure that the noise you are hearing is not just a normal limited slip differential noise. These rear LSD's make quite a racket in reverse. With a single mass flywheel, you really hear the noise this differential makes.
Check your suspension arms, bushings to ensure that they have not broken apart from the track use.
Let us know if any of these hit the mark.
fc-racer
1. Change your transmission oil to Swepco. Your track event might have overheated the fluid in there and you might not have the right viscosity anymore.
2. Check to ensure your clutch is operating correctly. Your dual mass flywheel might be broken. I think this was common enough that Porsche did a recall early in the car's life to update the part. My car had an updated flywheel when I bought it.
3. Ensure that the noise you are hearing is not just a normal limited slip differential noise. These rear LSD's make quite a racket in reverse. With a single mass flywheel, you really hear the noise this differential makes.
Check your suspension arms, bushings to ensure that they have not broken apart from the track use.
Let us know if any of these hit the mark.
fc-racer
02-10-2003, 11:48 PM
#6
Addict
Rennlist
Lifetime Member
Rennlist
Lifetime Member
Fc-racer,
Kevin's car is a '91 C2 Turbo. I don't think Swepco tranny fluid is a good idea. The swepco is very good for earlier and up to 915 tranny, I believe, or at least this is what I have learned on this forum.
I agree that Kevin should replace his tranny oil first and see if the noise stop. I have been used Mobil 1 tranny oil (synthetic) and have very good results (no strange noises), although I don't track my car, stree driving only.
I am with John's idea. I think that Kevin's car is having some issues with his limited slip differential based on his description. Maybe it is nothing, but it worths further looking in to.
Good luck Kevin, and please report back what the out come is.
Regards,
Sonny
Kevin's car is a '91 C2 Turbo. I don't think Swepco tranny fluid is a good idea. The swepco is very good for earlier and up to 915 tranny, I believe, or at least this is what I have learned on this forum.
I agree that Kevin should replace his tranny oil first and see if the noise stop. I have been used Mobil 1 tranny oil (synthetic) and have very good results (no strange noises), although I don't track my car, stree driving only.
I am with John's idea. I think that Kevin's car is having some issues with his limited slip differential based on his description. Maybe it is nothing, but it worths further looking in to.
Good luck Kevin, and please report back what the out come is.
Regards,
Sonny
03-01-2003, 07:46 PM
#7
Addict
Rennlist Member
Rennlist Member
Thread Starter
Hi Everyone
I promised to report back any findings...
I have not had the issue fixed yet, mainly because I have had to travel quite extensively since the clunking first occured.
However, I took the car out yesterday for a spin, and discovered the following:
- first, the clunking is worse.
- second, she's not performing like she usually does. Max boost seems to come on a little later (the shove in the pants usually happened around 3500rpm, and now it is more like 4500rpm). She seems to have power, but later and not as much...
If I may, here's a deeper description of the first:
When driving normally at around 100km/h, the clunking is not present;
When accelerating, the gear lever seems to 'jump' out of first as I pull it toward second.. hope that makes sense and there is a small clunk as it does so;
When I drive UP a 7 story car park, in first or second (third is too high a gear given the speeds in the car park), and I 'blip' the accelerator - give it a hard but short burst - then there is an audible, mechanical clunk, and I can feel it under my a$$;
When I drive DOWN the same car park, then firstly it is easier to produce the clucking sound, but more importantly, the clunking sound becomes a series of audible, mechanical clunks.. like something is settling down after being jolted. So instead of a single 'clunk', one can hear several clunks getting less audible as they become less 'violent'?
Gotta be honest, as a non-techy, I keep thinking the engine is about to fall out under the car... sounds almost like some bolt somewhere is loose.
This one's got me worried <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" /> <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />
I promised to report back any findings...
I have not had the issue fixed yet, mainly because I have had to travel quite extensively since the clunking first occured.
However, I took the car out yesterday for a spin, and discovered the following:
- first, the clunking is worse.
- second, she's not performing like she usually does. Max boost seems to come on a little later (the shove in the pants usually happened around 3500rpm, and now it is more like 4500rpm). She seems to have power, but later and not as much...
If I may, here's a deeper description of the first:
When driving normally at around 100km/h, the clunking is not present;
When accelerating, the gear lever seems to 'jump' out of first as I pull it toward second.. hope that makes sense
and there is a small clunk as it does so;When I drive UP a 7 story car park, in first or second (third is too high a gear given the speeds in the car park), and I 'blip' the accelerator - give it a hard but short burst - then there is an audible, mechanical clunk, and I can feel it under my a$$;
When I drive DOWN the same car park, then firstly it is easier to produce the clucking sound, but more importantly, the clunking sound becomes a series of audible, mechanical clunks.. like something is settling down after being jolted. So instead of a single 'clunk', one can hear several clunks getting less audible as they become less 'violent'?
Gotta be honest, as a non-techy, I keep thinking the engine is about to fall out under the car... sounds almost like some bolt somewhere is loose.
This one's got me worried <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" /> <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />
Trending Topics
03-01-2003, 07:51 PM
#8
Addict
Rennlist Member
Rennlist Member
Thread Starter
oh yeah...
and just to top it off, my 944S is undergoing a top-end rebuilt as we speak...
<img border="0" title="" alt="[Eek!]" src="eek.gif" /> <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />
and just to top it off, my 944S is undergoing a top-end rebuilt as we speak...
<img border="0" title="" alt="[Eek!]" src="eek.gif" /> <img border="0" alt="[crying]" title="" src="graemlins/crying.gif" />
03-01-2003, 09:18 PM
#9
Intermediate
Join Date: Feb 2002
Location: Northville, MI
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
How about checking those CV joints. If you grab the half-shaft there should be some movement transversally, that is to/from the wheel. However there should be no play radially, ie moving the wheel should move the axle, no play at all.
Note that you should check inboard (by the tranny) and outboard (by the wheel) CV joints.
The noise will often be a noise heard worst (or only) under load.
Just a thought.
Note that you should check inboard (by the tranny) and outboard (by the wheel) CV joints.
The noise will often be a noise heard worst (or only) under load.
Just a thought.
03-01-2003, 09:53 PM
#11
Intermediate
Join Date: Sep 2002
Location: Sydney, Australia
Posts: 27
Likes: 0
Received 0 Likes
on
0 Posts
Hi Kevin,
As you probably remember, I've had my 964 3.6 turbo now since August last year. There are certainly audible diff noises especialy when reversing slowly.
While moving forward, the cluncking noises occur particularly when going slowly around a corner exactly as you mentioned in a car park, I know this because I do it every morning.
When you back off the throttle and then lightly press again, the cluncking is evident.
It is particularly annoying because you need to constantly 'ride' the clutch when turning slowly as you cannot just leave it engaged say in first or second because the engine tend to jerk around 1200-1500 rpm resulting in diff cluncking.
The fact that first gear seems to want to jump out while shifting seems to me that the clutch is not disengaing completely, but I'm guessing here.
At the end of the day, it may well be that some part in the diff/gearbox has been on its way out, which under normal driving conditions may have gone unoticed for perhaps a couple of years, but the track event finaly caused pre-mature wear or failure.
If it is in fact getting worse [and not your imagination] then you know what has to be done, just make sure the workshop that pulls the gearbox down is trustworthy, or better still is a Porsche dealer [oops there goes the wallet], that way you have a comeback if the work is not performed satisfactorily.
Perhaps in a couple of more years I will have intimate mechanical knowledge with my 964 to answer your concern but at present it's only guesswork and gut feelings.
Hope the noises don't get worse!
Peter
964 3.6L Turbo
As you probably remember, I've had my 964 3.6 turbo now since August last year. There are certainly audible diff noises especialy when reversing slowly.
While moving forward, the cluncking noises occur particularly when going slowly around a corner exactly as you mentioned in a car park, I know this because I do it every morning.
When you back off the throttle and then lightly press again, the cluncking is evident.
It is particularly annoying because you need to constantly 'ride' the clutch when turning slowly as you cannot just leave it engaged say in first or second because the engine tend to jerk around 1200-1500 rpm resulting in diff cluncking.
The fact that first gear seems to want to jump out while shifting seems to me that the clutch is not disengaing completely, but I'm guessing here.
At the end of the day, it may well be that some part in the diff/gearbox has been on its way out, which under normal driving conditions may have gone unoticed for perhaps a couple of years, but the track event finaly caused pre-mature wear or failure.
If it is in fact getting worse [and not your imagination] then you know what has to be done, just make sure the workshop that pulls the gearbox down is trustworthy, or better still is a Porsche dealer [oops there goes the wallet], that way you have a comeback if the work is not performed satisfactorily.
Perhaps in a couple of more years I will have intimate mechanical knowledge with my 964 to answer your concern but at present it's only guesswork and gut feelings.
Hope the noises don't get worse!
Peter
964 3.6L Turbo
03-02-2003, 04:46 PM
#12
Addict
Rennlist Member
Rennlist Member
Thread Starter
Thanks for the replies!
I will have a look at the CV joints before I take the car into Porsche...
Peter... we must try to grab that beer next I'm in Sydney. I'll let you know. PS - the Cayenne is not at the Melbourne Motor Show! And neither are Porsche. But tomorrow night I've been invited to their 911 Celebration Event.
Oh yeah - and I will be at the Melbourne F1 GP Thursday thru Sunday!
Cheers!
I will have a look at the CV joints before I take the car into Porsche...
Peter... we must try to grab that beer next I'm in Sydney. I'll let you know. PS - the Cayenne is not at the Melbourne Motor Show! And neither are Porsche. But tomorrow night I've been invited to their 911 Celebration Event.
Oh yeah - and I will be at the Melbourne F1 GP Thursday thru Sunday!
Cheers!
03-30-2003, 05:03 AM
#13
Addict
Rennlist Member
Rennlist Member
Thread Starter
Hello Everyone!!
Been 'offline' for some time while the car was in the workshop... promised to post an update when I got it back, so here goes...
The 'clunking' sound was diagnosed to be a combination of the Limited Slip Diff Clutch Assembly and play in the two rear drive shafts. This was all replaced, and the sound is definately better - much better in fact - but there is still a slight clunk left.
The clunk is noticable when changing from 1st to 2nd under load.. ie accelerate (not flat out but hard all the same) and at around 4500 rpm clutch in to change... gear lever seems to 'jump' out of 1st as I pull it back into second, and there is an audible clunk (I can also feel the clunk through the bodywork of the car).
Also, the clunk is noticable when in second and giving the car a 'squirt' and then coming off the accelerator.
Another way to replicate the clunck is in a car park as posted before...
Gotta say, this one's got everyone nailed
So, here's a competition... the person with the closest 'clue' gets a beer next time I'm in your neck of the woods... <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
Take Care everyone!
Been 'offline' for some time while the car was in the workshop... promised to post an update when I got it back, so here goes...
The 'clunking' sound was diagnosed to be a combination of the Limited Slip Diff Clutch Assembly and play in the two rear drive shafts. This was all replaced, and the sound is definately better - much better in fact - but there is still a slight clunk left.
The clunk is noticable when changing from 1st to 2nd under load.. ie accelerate (not flat out but hard all the same) and at around 4500 rpm clutch in to change... gear lever seems to 'jump' out of 1st as I pull it back into second, and there is an audible clunk (I can also feel the clunk through the bodywork of the car).
Also, the clunk is noticable when in second and giving the car a 'squirt' and then coming off the accelerator.
Another way to replicate the clunck is in a car park as posted before...
Gotta say, this one's got everyone nailed
So, here's a competition... the person with the closest 'clue' gets a beer next time I'm in your neck of the woods... <img border="0" alt="[cheers]" title="" src="graemlins/beerchug.gif" />
Take Care everyone!
