E46 Gear Change Clunk
Discussion
Paul M said:
I recently contacted BMW (UK) who in turn spoke with the dealer. This is their reply to me after speaking with the dealer;
"Upon receipt of your communication, I contacted Mr- -, Workshop Controller at - in -. Mr - has confirmed that initially the flywheel of your vehicle was replaced as this was though to be causing the noise you describe. However, you soon reported that the noise was still present.
Mr - then accompanied you on a test drive and determined that the noise is only apparent when the vehicle is sat idle and first gear is selected. This noise occurs when the drive train first becomes active. Mr - then tested this on other vehicles of a similar age to yours and found that the noise was present with them too. As a result, Mr - could only recommend that the noise is normal and that you monitor the noise".
1. I was not accompanied on a test drive. I demonstrated the noise sat in the car with the WC and explained the noise when driving and changing from 1st to 2nd gear
2. The noise is not only apparent when the vehicle is sat at idle (As 1 above)
3. Which vehicles of a similar age? I wasn't told that by the WC
4. If the noise is "normal" (after demonstrating to the WC how "violent" the noise at idle can be and feeling it through the seat) then all similar vehicles must suffer from it - Which they don't!
I'd have thought, with access to a lift and full workshop facilities, they'd be able to trace the source of the noise within a few minutes. I traced mine to the rear axle area, and since it:"Upon receipt of your communication, I contacted Mr- -, Workshop Controller at - in -. Mr - has confirmed that initially the flywheel of your vehicle was replaced as this was though to be causing the noise you describe. However, you soon reported that the noise was still present.
Mr - then accompanied you on a test drive and determined that the noise is only apparent when the vehicle is sat idle and first gear is selected. This noise occurs when the drive train first becomes active. Mr - then tested this on other vehicles of a similar age to yours and found that the noise was present with them too. As a result, Mr - could only recommend that the noise is normal and that you monitor the noise".
1. I was not accompanied on a test drive. I demonstrated the noise sat in the car with the WC and explained the noise when driving and changing from 1st to 2nd gear
2. The noise is not only apparent when the vehicle is sat at idle (As 1 above)
3. Which vehicles of a similar age? I wasn't told that by the WC
4. If the noise is "normal" (after demonstrating to the WC how "violent" the noise at idle can be and feeling it through the seat) then all similar vehicles must suffer from it - Which they don't!
a) Didn't seem like a particularly malignant mechanical noise
b) Was present on other similar cars I'd driven
and
c) Was uncomfortable laying on my back under a running car being knocked in and out of gear - one confused clutch release and I'd have been squashed.
I decided to leave it and put up with it. The chances are even if you fix it, it will return.
Paul M said:
4. If the noise is "normal" (after demonstrating to the WC how "violent" the noise at idle can be and feeling it through the seat) then all similar vehicles must suffer from it - Which they don't!
The version I got from My BMW Dealership was along the lines of: "Some cars have the clunk, some cars don't, and the cause has never been found. We could replace items on the car to try and track down the issue, but to be honest, it won't make the car any more reliable and it could cost a lot of money. If you can live with it, save your money!"
(Be aware that I have known these guys for @ 25years and they look after Me very well! They could have easily gone down the "We need to replace parts" route and could have had a shed load of money off Me, but they were honest enough to advise Me that it wasn't worth going down that route really).
4rephill said:
The version I got from My BMW Dealership was along the lines of:
"Some cars have the clunk, some cars don't, and the cause has never been found. We could replace items on the car to try and track down the issue, but to be honest, it won't make the car any more reliable and it could cost a lot of money. If you can live with it, save your money!"
(Be aware that I have known these guys for @ 25years and they look after Me very well! They could have easily gone down the "We need to replace parts" route and could have had a shed load of money off Me, but they were honest enough to advise Me that it wasn't worth going down that route really).
As my vehicle is still under AUC Warranty it's best anything that may be replaced is done now rather than the potential large expense once the car is out of warranty."Some cars have the clunk, some cars don't, and the cause has never been found. We could replace items on the car to try and track down the issue, but to be honest, it won't make the car any more reliable and it could cost a lot of money. If you can live with it, save your money!"
(Be aware that I have known these guys for @ 25years and they look after Me very well! They could have easily gone down the "We need to replace parts" route and could have had a shed load of money off Me, but they were honest enough to advise Me that it wasn't worth going down that route really).
I appreciate (and the odds are probably against) that the issue probably won't be resolved and I'll have to live with it but at this time there's nothing to loose trying
Found this on another forum.
I know that the M3 suffers from (quite commonly) the thumping issue.
I'm certainly not mechanically minded enough to know if this is the cause and the M3 diff and mechanicals etc would be completely different to my 320.
"E46 M3 - "Clunk Noise" on Load Reversal MODEL
E46 M3 with S54 engine SITUATION
Customer may complain of a drivetrain rattle or knocking noise during a load change, e.g. 1st to 2nd gearshift at low engine speed, coming from the rear axle area. Further drivetrain checks reveal that the right side rear axle output flange appears to have more play (approximately 0.5mm to almost 1mm) when compared to the left side output flange. INFORMATION
The radial play on the right side rear axle flange is a normal design characteristic of the new M differential lock style rear axle used on E46 M3 models. Therefore an M3 differential should not be replaced due to a difference in play (when comparing left to right side differential output flange play) since this will not eliminate a drivetrain rattle or knocking noise. IMPORTANT
In order to transmit engine torque to the rear wheels instantaneously, without any time lag, the whole M3 power train was designed with maximum torsional rigidity. Consequently, the flywheel mass and its damping capability has been reduced to a minimum. As a result, during an abrupt torque transfer (e.g. 1st to 2nd gearshift at low engine speeds) driver receives an acoustic feedback, which can be interpreted as a "clunking or rattling" noise. This characteristic is common in many high performance vehicles. Activation of the "Sport Mode" offers an additional increase in driving dynamics. As a result, acoustic feedback from the power train may be even more pronounced. The acoustic feedback characteristic is not a symptom of a failure, and does not compromise long-term reliability of drivetrain components (clutch, transmission, differential), nor does it adversely affect performance of the vehicle. WARRANTY INFORMATION"
I know that the M3 suffers from (quite commonly) the thumping issue.
I'm certainly not mechanically minded enough to know if this is the cause and the M3 diff and mechanicals etc would be completely different to my 320.
"E46 M3 - "Clunk Noise" on Load Reversal MODEL
E46 M3 with S54 engine SITUATION
Customer may complain of a drivetrain rattle or knocking noise during a load change, e.g. 1st to 2nd gearshift at low engine speed, coming from the rear axle area. Further drivetrain checks reveal that the right side rear axle output flange appears to have more play (approximately 0.5mm to almost 1mm) when compared to the left side output flange. INFORMATION
The radial play on the right side rear axle flange is a normal design characteristic of the new M differential lock style rear axle used on E46 M3 models. Therefore an M3 differential should not be replaced due to a difference in play (when comparing left to right side differential output flange play) since this will not eliminate a drivetrain rattle or knocking noise. IMPORTANT
In order to transmit engine torque to the rear wheels instantaneously, without any time lag, the whole M3 power train was designed with maximum torsional rigidity. Consequently, the flywheel mass and its damping capability has been reduced to a minimum. As a result, during an abrupt torque transfer (e.g. 1st to 2nd gearshift at low engine speeds) driver receives an acoustic feedback, which can be interpreted as a "clunking or rattling" noise. This characteristic is common in many high performance vehicles. Activation of the "Sport Mode" offers an additional increase in driving dynamics. As a result, acoustic feedback from the power train may be even more pronounced. The acoustic feedback characteristic is not a symptom of a failure, and does not compromise long-term reliability of drivetrain components (clutch, transmission, differential), nor does it adversely affect performance of the vehicle. WARRANTY INFORMATION"
Paul M said:
Found this on another forum.
I know that the M3 suffers from (quite commonly) the thumping issue.
I'm certainly not mechanically minded enough to know if this is the cause and the M3 diff and mechanicals etc would be completely different to my 320.
"E46 M3 - "Clunk Noise" on Load Reversal MODEL
E46 M3 with S54 engine SITUATION
Customer may complain of a drivetrain rattle or knocking noise during a load change, e.g. 1st to 2nd gearshift at low engine speed, coming from the rear axle area. Further drivetrain checks reveal that the right side rear axle output flange appears to have more play (approximately 0.5mm to almost 1mm) when compared to the left side output flange. INFORMATION
The radial play on the right side rear axle flange is a normal design characteristic of the new M differential lock style rear axle used on E46 M3 models. Therefore an M3 differential should not be replaced due to a difference in play (when comparing left to right side differential output flange play) since this will not eliminate a drivetrain rattle or knocking noise. IMPORTANT
In order to transmit engine torque to the rear wheels instantaneously, without any time lag, the whole M3 power train was designed with maximum torsional rigidity. Consequently, the flywheel mass and its damping capability has been reduced to a minimum. As a result, during an abrupt torque transfer (e.g. 1st to 2nd gearshift at low engine speeds) driver receives an acoustic feedback, which can be interpreted as a "clunking or rattling" noise. This characteristic is common in many high performance vehicles. Activation of the "Sport Mode" offers an additional increase in driving dynamics. As a result, acoustic feedback from the power train may be even more pronounced. The acoustic feedback characteristic is not a symptom of a failure, and does not compromise long-term reliability of drivetrain components (clutch, transmission, differential), nor does it adversely affect performance of the vehicle. WARRANTY INFORMATION"
I clearly remember hearing the same type of thump on late '80's early 90's era F1 cars under certain conditions (usually when the wind was taking some of the exhaust noise away). It was a kind of muffled short boom during gearchanges.I know that the M3 suffers from (quite commonly) the thumping issue.
I'm certainly not mechanically minded enough to know if this is the cause and the M3 diff and mechanicals etc would be completely different to my 320.
"E46 M3 - "Clunk Noise" on Load Reversal MODEL
E46 M3 with S54 engine SITUATION
Customer may complain of a drivetrain rattle or knocking noise during a load change, e.g. 1st to 2nd gearshift at low engine speed, coming from the rear axle area. Further drivetrain checks reveal that the right side rear axle output flange appears to have more play (approximately 0.5mm to almost 1mm) when compared to the left side output flange. INFORMATION
The radial play on the right side rear axle flange is a normal design characteristic of the new M differential lock style rear axle used on E46 M3 models. Therefore an M3 differential should not be replaced due to a difference in play (when comparing left to right side differential output flange play) since this will not eliminate a drivetrain rattle or knocking noise. IMPORTANT
In order to transmit engine torque to the rear wheels instantaneously, without any time lag, the whole M3 power train was designed with maximum torsional rigidity. Consequently, the flywheel mass and its damping capability has been reduced to a minimum. As a result, during an abrupt torque transfer (e.g. 1st to 2nd gearshift at low engine speeds) driver receives an acoustic feedback, which can be interpreted as a "clunking or rattling" noise. This characteristic is common in many high performance vehicles. Activation of the "Sport Mode" offers an additional increase in driving dynamics. As a result, acoustic feedback from the power train may be even more pronounced. The acoustic feedback characteristic is not a symptom of a failure, and does not compromise long-term reliability of drivetrain components (clutch, transmission, differential), nor does it adversely affect performance of the vehicle. WARRANTY INFORMATION"
This is what makes me think it could be a synchro issue causing an audiable jolt somewhere in the drivetrain.
I'm sure on my car now that the clunk when engaging 1st is coming from the rearmost UJ in the propshaft. I managed to get a video of it, here I was just twisting the prop at the gearbox end with one hand whilst filming the joint with the other. You can imagine that with friction or inertia turning the gearbox with any kind of speed or force the clunk would be that much more violent.
One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
buggalugs said:
I'm sure on my car now that the clunk when engaging 1st is coming from the rearmost UJ in the propshaft. I managed to get a video of it, here I was just twisting the prop at the gearbox end with one hand whilst filming the joint with the other. You can imagine that with friction or inertia turning the gearbox with any kind of speed or force the clunk would be that much more violent.
One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
What vehicle is your clunk on?One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
Has it worsened over time?
Paul M said:
buggalugs said:
I'm sure on my car now that the clunk when engaging 1st is coming from the rearmost UJ in the propshaft. I managed to get a video of it, here I was just twisting the prop at the gearbox end with one hand whilst filming the joint with the other. You can imagine that with friction or inertia turning the gearbox with any kind of speed or force the clunk would be that much more violent.
One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
What vehicle is your clunk on?One thing's for sure, I need a new prop, and sooner rather than later!
http://youtu.be/cfFndio2hck?hd=1
Has it worsened over time?
I would say yes
buggalugs said:
E46 328i Manual
I would say yes
A bit disconcerting that you say the symptoms have worsened. Then again I don't know the exact symptoms you have, if they are the same as I have, how long you've had them etc.I would say yes
I've noticed mine now clunks when engaging reverse from standstill and 1st to 4th gears. Nothing when the clutch is depressed all of the time.
I have a letter published in this months BMW Car mag outlining the issue. They asked a BMW specialist (BM Sport) who stated the thump is general play in the drivetrain and is worse in some cars than others (I still wonder why that is) Also suggested changing the gearbox oil and have the hydraulic system bled.
I get the same sort of issues in my Z4 Coupe 3.0si. I'm glad I'm not alone!
Regarding the 1st to 2nd issue, markc123's comment about a vacuum leak my have merit in my case. I do sometimes get erratic throttle behaviour at low revs (only sometimes) and the revs do drop quite suddenly when changing gear. Infact I can smooth out 1st to 2nd by revving it higher than normal. Might be worth getting it checked for a vacuum leak, would it show as an OBD code?
I don't think I have any clutch drag but I do sometimes get a bit of clutch judder if setting off quickly when it's cold.
Regarding the 1st to 2nd issue, markc123's comment about a vacuum leak my have merit in my case. I do sometimes get erratic throttle behaviour at low revs (only sometimes) and the revs do drop quite suddenly when changing gear. Infact I can smooth out 1st to 2nd by revving it higher than normal. Might be worth getting it checked for a vacuum leak, would it show as an OBD code?
I don't think I have any clutch drag but I do sometimes get a bit of clutch judder if setting off quickly when it's cold.
Mackie - vac leaks sometimes show up as lean codes, or in the long term fuel trims.
On the E46, you can simply drive with the MAF disconnected for a bit and see if the problem goes away. Other reasons for bouncy idling seem to centre round the VANOS system.
Buggalugs - the rear UJ also has a rubber coupling or guibo, common wear item and can cause jerks on changes. Needs doing on mine.
On the E46, you can simply drive with the MAF disconnected for a bit and see if the problem goes away. Other reasons for bouncy idling seem to centre round the VANOS system.
Buggalugs - the rear UJ also has a rubber coupling or guibo, common wear item and can cause jerks on changes. Needs doing on mine.
Edited by markc123 on Monday 24th September 17:01
Paul M said:
buggalugs said:
E46 328i Manual
I would say yes
A bit disconcerting that you say the symptoms have worsened. Then again I don't know the exact symptoms you have, if they are the same as I have, how long you've had them etc.I would say yes
I've noticed mine now clunks when engaging reverse from standstill and 1st to 4th gears. Nothing when the clutch is depressed all of the time.
I have a letter published in this months BMW Car mag outlining the issue. They asked a BMW specialist (BM Sport) who stated the thump is general play in the drivetrain and is worse in some cars than others (I still wonder why that is) Also suggested changing the gearbox oil and have the hydraulic system bled.
I am not looking for any ghosts here, I could go to the trouble of replacing the half shafts to eliminate more play but I'm just going to live with it I think.
Paul M said:
I can live with it although can't say I accept it.
Frustrating that there is no real cure.
Have a service due soon and probably have gearbox oil changed as well to see if it makes any difference.
I'm sure if you replaced enough parts you could cure it, it's just not worth the cost in reality.Frustrating that there is no real cure.
Have a service due soon and probably have gearbox oil changed as well to see if it makes any difference.
As for:
Paul M said:
I can live with it although can't say I accept it.
Whilst you'll forever be thinking: "It can't be right!", eventually you will reluctantly "accept it". You'll end up telling people: "Some do it, some don't, it just the way they are!" ( Welcome to My world!
)Paul M said:
I can live with it although can't say I accept it.
Frustrating that there is no real cure.
Have a service due soon and probably have gearbox oil changed as well to see if it makes any difference.
Gearbox oil change did the last one a world of good for 1000 miles or so then it was back. Current one didn't have it when I bought it, but has slowly started creeping in.. Maybe it's a driver thing?Frustrating that there is no real cure.
Have a service due soon and probably have gearbox oil changed as well to see if it makes any difference.
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