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'03 330Ci, '05 ZHP 330i 6MT, 996 GT3, Audi SQ5
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Discussion Starter · #1 ·
Howdy Gang-

Found my son one sweet ZHP last summer with 145k miles and everything from coolant lines under the intake to new windshield/cowl/Michelin PS4's made it even sweeter.

One curiosity is we've got some tranny chatter as the motor turns off when in neutral. If I engage the clutch and turn the engine off, no chatter. Trying to figure out what's knocking around in the gearbox creating the chatter. I've seen a couple threads speaking to dual mass flywheel and just holding the clutch in, but nothing definitive about what's getting knocked around. I doubt it happened when new so what's worn that gives me a good excuse to drop the tranny and dive in?

Appreciate the help-

~John

Wheel Tire Car Cloud Vehicle
 

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Trying to figure out what's knocking around in the gearbox creating the chatter.
The dual mass flywheel has 2 big pieces of mass, coupled loosely with about 3/4 to 1" rotational arc plays. So it is not unusual for the loose mass (flywheel + PP) to rock back/fore when the crank is jerking around during shutting down. Step on the clutch helps to damp the oscillation because the TOB presses on the PP and creates the resistance for the oscillation. Don't worry, wait until replace the clutch then check for the DMF for excessive rotational plays (if more than 1" arc)
BTW, engine is shut off with clutch pedal down most of the time anyway.
 

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'03 330Ci, '05 ZHP 330i 6MT, 996 GT3, Audi SQ5
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Discussion Starter · #3 ·
Great explanation- thank you. Won't worry then about the tranny grenading on my son somewhere leaving him stranded. Will be a good project come clutch time and I'll have him clutch it on shutdowns tween now and then. Cheers!
 

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Nice ride, Nice purchase.

I don't think it's going to grenade on you.

I have a slightly different take. I have pulled and tested several dual mass flywheels.
Sapote is correct that they are designed to rotate 3/4 to 1 inch but even with 200k miles + they will usually not have "loose" rotational play..not to the point of making a rattling noise.

Occasionally you will have axial play in the DMF (in/out or front/back) that could make a noise, but that is also relatively uncommon.

Please see an excellent video on what a bad DMF looks and sounds like. He shows how to measure rotational play at 2:25 or so...And Axial play is shown at 3:25..but watch the whole thing.

Any chance a previous owner replaced the clutch and flywheel? People often put in things like single mass flywheels, lightweight flywheels, non self-adjusting clutches, etc. Many of these end up making noise.

I guess I would keep an eye on it, and consider when or if to change the clutch and/or flywheel.
 

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The gearbox itself has clearances inside ti that will rattle, too.

My tired 5- speed will make a bit of 'getrag rattle' when I switch off
in netural as well- and I have a SMF...

t
 

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Any chance a previous owner replaced the clutch and flywheel? People often put in things like single mass flywheels, lightweight flywheels, non self-adjusting clutches, etc. Many of these end up making noise.
One way to find out if it has single mass FW: shift in 5th or 6th gear, pull hand brake, then try to rotate the crank back/fore and see how much rotational plays. Double mass has more plays than single mass.
 

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Mine's been doing that since I bought it from PO. 70k miles later it's been fine. I've gotten used to just pressing in the clutch to shut off the engine. This car is also the car I learned how to drive stick in, so it's not like I've been super kind to it.
 
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