Please help me diagnose this noise.

Couzens · Post by **Couzens** » Tue Aug 22, 2017 9:33 pm

Car is up for sale and has just developed an odd knocking which sounds like it's coming from the gear box. The car is booked into have a checker and drive tomorrow prior to being sold, but I've now noticed this...

https://youtu.be/8I8lXWIBfJg

Any help would be appreciated.

jamie_z4 · Post by **jamie_z4** » Tue Aug 22, 2017 9:34 pm

That sounds like the usual dmf rattling it's tits off

mr wilks · Post by **mr wilks** » Tue Aug 22, 2017 10:26 pm

jamie_z4 wrote: ↑Tue Aug 22, 2017 9:34 pm That sounds like the usual dmf rattling it's tits off

Yep agreed , don't rev it , depress the clutch & it should change tone

Marlon · Post by **Marlon** » Tue Aug 22, 2017 10:30 pm

Mine does that too - on idle, then goes quiet when clutch depressed. What's a dmf ?

Couzens · Post by **Couzens** » Tue Aug 22, 2017 10:32 pm

Dual Mass Flywheel. What a time for it to go. Looks like new clutch and DMF time then?

Marlon · Post by **Marlon** » Tue Aug 22, 2017 10:34 pm

surely it doesn't mean its gone! Just another Zed noise that everyone has?

mr wilks · Post by **mr wilks** » Tue Aug 22, 2017 10:35 pm

Marlon wrote: ↑Tue Aug 22, 2017 10:30 pm Mine does that too - on idle, then goes quiet when clutch depressed. What's a dmf ?

Dual mass flywheel that is part of the clutch set up .
I did have a Z with the above noise , my indy talked me out of replacing clutch + DMF saying it was most likely that way for the last 30k miles & will most likely be the same after another 30k , , performance was not affected to the best of my knowledge

Marlon · Post by **Marlon** » Tue Aug 22, 2017 10:36 pm

mr wilks wrote: ↑Tue Aug 22, 2017 10:35 pm
Marlon wrote: ↑Tue Aug 22, 2017 10:30 pm Mine does that too - on idle, then goes quiet when clutch depressed. What's a dmf ?
Dual mass flywheel that is part of the clutch set up .
I did have a Z with the above noise , my indy talked me out of replacing clutch + DMF saying it was most likely that way for the last 30k miles & will most likely be the same after another 30k , , performance was not affected to the best of my knowledge

Good. Just another little quirk like the ticking N52 block

Next time we meet you can have a listen see if its the same noise - may not be

MACK · Post by **MACK** » Tue Aug 22, 2017 11:35 pm

Dmf is an awkward one when selling, not cost effective to fix for a bit of noise, it's when you start to feel it that most people replace them with the clutch as a combo. Even then they can still last forever and a day. Friend on mine has a diesel audi that had a Dmf noise since 110k, it's now on 175k and it's 6 years later and it's still going strong.

My advice would be to leave it and be prepared for someone to talk you down a bit, if they even notice it. You may be suprised, alot of folks dont.

jamie_z4 · Post by **jamie_z4** » Wed Aug 23, 2017 6:07 am

My coupe did it. It's not ideal but as wilksy said it's probably fine for a long time to come.

ph001 · Post by **ph001** » Wed Aug 23, 2017 9:52 am

I wouldn't be worried about that at all tbh. Most people would consider it quite normal.

Roundozo · Post by **Roundozo** » Wed Aug 23, 2017 1:42 pm

Mine did it before I replaced clutch and dmf last year and is doing it again now. Nothing to worry about. Not a N52 quirk but a general BMW one. My old 3 series did exactly the same and had been to the moon and back. Unless you're getting clutch slip, best leave it be.

Buckz · Post by **Buckz** » Wed Aug 23, 2017 1:44 pm

mine has been doing it since day one, I did know what it was so it never worried me.

Couzens · Post by **Couzens** » Wed Aug 23, 2017 5:10 pm

Thanks for the advice chaps.

groovy_hippy · Post by **groovy_hippy** » Wed Aug 23, 2017 7:11 pm

Mine does that too. Put the clutch down at idle and it'll stop. My Mini One did the same (also with a DMF I believe). I was told at the time it's the clutch release bearing and nothing to worry about until you have difficulty getting the thing into gear...

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