Transmission rattling noise when gradually accelerating from low revs
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03-22-2013, 11:04 PM
#17
Drifting
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PK, the stock clutch disk is sprung. The springs will make noise till the point that the engine has enough torque to yield coil bind and rotate the disk. With the dual mass flywheel the sound that you hear a dull rattle can be heard in a few situations. More miles on the car, heavy street stop and go driving, and/or someone that rides the clutch pedal. This noise is similar to what you will hear with a LWFW install. Once you are up and running typically past 1800 to 2500 RPM's the noise goes away.
I doubt that it's your tranny, you would hear the noise thru the entire RPM range. Interesting, most new owners complain about the intermediate shaft noise..
I doubt that it's your tranny, you would hear the noise thru the entire RPM range. Interesting, most new owners complain about the intermediate shaft noise..
Engine lugging or clutch springs. It sounds like there is nothing really wrong. Just getting used to a car that is a little different from other cars. It took about 6 months before I was really comfortable with it. They like to operate above 2500 rpm. Actually, they are happiest above 3500 rpm.
03-22-2013, 11:34 PM
#18
Instructor
Thread Starter
Once again, thank you very much for your feedback guys.
I just went for a ride, I adjusted my driving style (I tried not to get the engine reving below 2000rpm) and everything went smoothly!
So, as SSST said, it seems like I just need to get used to the car. I'll keep you posted if there is actually something wrong (other than the driver).
I just went for a ride, I adjusted my driving style (I tried not to get the engine reving below 2000rpm) and everything went smoothly!
So, as SSST said, it seems like I just need to get used to the car. I'll keep you posted if there is actually something wrong (other than the driver).
03-22-2013, 11:48 PM
#19
Instructor
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Between 6000-7000rpm during acceleration the back end of my car is not inline with the front (crabbing almost) and I get this burning smell inside the car. Can't quite put my finger on what the problem is. This also makes the passenger in the car quite nervous. Any thoughts would be appreciated.
03-23-2013, 12:12 AM
#20
Drifting
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Between 6000-7000rpm during acceleration the back end of my car is not inline with the front (crabbing almost) and I get this burning smell inside the car. Can't quite put my finger on what the problem is. This also makes the passenger in the car quite nervous. Any thoughts would be appreciated.
On edit: one thing I've figured out over the last 2 years is that every one of these cars is a little bit different. There is a much wider range of "normal" with respect to quirks than there is with higher volume production cars.
Last edited by SSST; 03-23-2013 at 12:57 AM.
07-24-2013, 07:38 PM
#21
Rennlist Member
Dredging up an old posting...is it possible to tell if you have a LWFW on a car without actually seeing it? I bought the car from a dealer that was on trade, so I don't know the PO.
I've always held a slight suspicion that it had one, just couldn't ever figure out a way to confirm it. My car purrs like a kitten when not in gear, but gets quite chatty in gear in city driving. The dealer told me that PO had just put in a "new clutch" when I bought it.
Suuuuure, that's what they all say lol
I've always held a slight suspicion that it had one, just couldn't ever figure out a way to confirm it. My car purrs like a kitten when not in gear, but gets quite chatty in gear in city driving. The dealer told me that PO had just put in a "new clutch" when I bought it.
Suuuuure, that's what they all say lol
07-24-2013, 09:17 PM
#22
Instructor
Thread Starter
I don't know if there is an easy way to tell if you have a LWFW without seeing it (Kevin may have some insights on this) but here is a thread where I found the answer to my question and that may explain why your car is chatty in city driving: http://www.6speedonline.com/forums/9...aft-noise.html
07-25-2013, 01:35 PM
#24
OK boys, one more consideration. I had a DM flywheel go bad and at idle it sounded just like a LW flywheel. Even my shop that installed the clutch 6 years ago said it was a LWFW until I said no no no! Well I installed a LWFW and all is good. To the OP your DMFW may be going bad, Mike
07-28-2013, 06:29 AM
#25
Burning Brakes
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My money is on normal. What you are hearing is the front diff and cardan shaft. Sounds like gearbox but it ain't. Where they marry together there is some play - even when new (in my case - I was back and forth to dealer about this). When you lug the engine they resonate. To test; drive in 5th/6th and lug the engine at 2K - in this range it is most notable. Once at 2.5-3K if it goes away, there you go. As I was making such a fuss with a dealer, I received a letter from Porsche Stuttgart confirming this is normal.
07-28-2013, 01:38 PM
#26
Rennlist Member
My money is on normal. What you are hearing is the front diff and cardan shaft. Sounds like gearbox but it ain't. Where they marry together there is some play - even when new (in my case - I was back and forth to dealer about this). When you lug the engine they resonate. To test; drive in 5th/6th and lug the engine at 2K - in this range it is most notable. Once at 2.5-3K if it goes away, there you go. As I was making such a fuss with a dealer, I received a letter from Porsche Stuttgart confirming this is normal.
I'm gonna guess if you have a lwfw, the noise that it makes can be made in neutral. Since I don't ever hear it in neutral, your explanation makes sense.
06-18-2015, 04:23 PM
#27
Rennlist Member
PK, the stock clutch disk is sprung. The springs will make noise till the point that the engine has enough torque to yield coil bind and rotate the disk. With the dual mass flywheel the sound that you hear a dull rattle can be heard in a few situations. More miles on the car, heavy street stop and go driving, and/or someone that rides the clutch pedal. This noise is similar to what you will hear with a LWFW install. Once you are up and running typically past 1800 to 2500 RPM's the noise goes away.
I doubt that it's your tranny, you would hear the noise thru the entire RPM range. Interesting, most new owners complain about the intermediate shaft noise..
I doubt that it's your tranny, you would hear the noise thru the entire RPM range. Interesting, most new owners complain about the intermediate shaft noise..
06-19-2015, 12:27 PM
#28
Race Director
I'm glad to read this as I stared developing the same noise in my 03 now that I've been driving it quite a bit. Changed the boxes to Delvac just to make sure and still hear it. Sounds like a clicking noise up to a little over 2k when going very light throttle but goes away under harder acceleration.
As an aside, the only odd sounds my Turbo makes is when I drive at low speed in too high a gear. I try to avoid doing this and am successful so it I do not have a real good description of the noise other than it is a rather unpleasant sound, almost a groan, and I quickly adapted a driving style that avoids subjecting the car to the conditions that produce this noise.
For slow speed driving I use 1st gear and try to arrange things so I do not have to slip the clutch to maintain forward momentum. In other gears I keep RPMs above 2K and in the highest gears I try to stay at or above 2500 RPMs.
In spite of the engine's torque it is not a truck engine and I avoid too low of RPM operation with load.
01-19-2017, 02:31 PM
#29
Pro
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I didn't see this as a solution so I'm posting even though I have a lowly NA. My mechanic swapped out the gearbox oil and about 90% of the transmission rattle went away (slight gearbox rattles are normal I'm told). Mine was rattling primarily when pulling away from a stop. He indicated the old gear oil was toast. Even though it's DIY, you might want to have the mechanic do it so he can peak inside the gearbox to check if looks ok - I'm guessing my mechanice did it with a borescope.
My car only has 24K miles. As with other things on an old car, it seems like you can't leave it alone just because the miles are low.
My car only has 24K miles. As with other things on an old car, it seems like you can't leave it alone just because the miles are low.
01-22-2017, 11:09 PM
#30
I didn't see this as a solution so I'm posting even though I have a lowly NA. My mechanic swapped out the gearbox oil and about 90% of the transmission rattle went away (slight gearbox rattles are normal I'm told). Mine was rattling primarily when pulling away from a stop. He indicated the old gear oil was toast. Even though it's DIY, you might want to have the mechanic do it so he can peak inside the gearbox to check if looks ok - I'm guessing my mechanice did it with a borescope.
My car only has 24K miles. As with other things on an old car, it seems like you can't leave it alone just because the miles are low.
My car only has 24K miles. As with other things on an old car, it seems like you can't leave it alone just because the miles are low.
You know this thread is years old, right?
