Driveline noise

[Skylarking]

^ was that in your modded VE or on a standard VF2.

I’d think that the bolts should have been engineered strong enough not to bend and if they bent in a standard vehicle they are not fit for use

 

[eman1]

Yep there's 3 somehow mine were bent giving slop and thud sound

I'll check it out, very possible considering mine has been used at the drag strip and the track.

I'd love to have that factory tight feeling again.

 

[Anthony121]

Recalls & faults: Holden VF Commodore (2013-2017)

2015 Holden VF Commodore: clunk when shifting between drive and reverse
General Motors issued a service bulletin for 2015 Holden VF Commodore vehicles that had six-speed 6L45 MYA automatic transmissions. In these vehicles, a 'clunk' or 'ping' noise may be heard from the rear of the vehicle when the driver completed a 'change of direction shift' (i.e. drive to reverse or reverse to drive). The service bulletin attributed this noise to movement between the splines of the output shaft and the output flange. Furthermore, this noise could 'propagate' up the prop shaft and the transmission tunnel to the rear of the vehicle. To fix,

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  • The propeller shaft was to be removed;

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  • The transmission output nut and flange were to be removed, and the output shaft flange nut discarded. The transmission output flange was then to be removed from the transmission output shaft;

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  • The output flange and shaft were to be inspected for corrosion and, if present, that corrosion was to be removed with a wire brush. The parts were then to be cleaned with Prepsol, wiped thoroughly and allowed to fully dry;

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  • The output flange was to be re-installed with adhesive (GM part number 89021297) or Loctite 272 applied across the width of the flange splines. Once adhesive had been applied to every spline along its complete length, the output flange was to be installed over the shaft. Excessive adhesive was to be wiped off with a clean rag;

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  • The new output flange nut was to be cleaned (with Prepsol if required);

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  • The output flange nut was to be installed with adhesive across the thread of the new nut;

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  • The propeller shaft was to be re-installed; and,

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  • The vehicle was to be left for 24 hours so that the adhesive could cure.

Holden VF Commodore with six-speed auto: clunk noise on take-off
General Motors issued a service bulletin for Holden VF Commodore vehicles that had six-speed automatic transmissions. When accelerating from rest under light to medium throttle, the driver may notice a 'thud' or 'clunk' noise from the rear of the vehicle immediately after take-off. According to the service bulletin, the noise would only be heard when moving forward in Drive mode or Sports mode, but would not be experienced in Active Select (A/S) mode.

The clunk noise was attributed to the transmission making a clutch change while in first gear. Specifically, the transmission changed from a first locked (CBR1 clutch locked) to a first freewheel (CBR1 clutch released) state at 4 km/h. The driver does not usually feel the clutch transition of CBR1 releasing since the first gear ratio was maintained. However, the disengagement of the CBR1 clutch and the engagement of the one-way clutch caused a torque-spike that could produce a clunk noise at the driveline end of the vehicle.

According to the service bulletin, owners were to be informed that the noise was a 'known, normal characteristic of the transmission' and that it was 'not detrimental to the life of the vehicle'.

That last paragraph can be a problem with lazy dealers that simply don’t want to investigate further and just dismiss the noise.

Best to gather as much detail as possible about the noise, where it comes from and under what conditions. If you have a copy of the VF workshop manual, it has a great section that defines the noise terminology that the service guys should be using... read it and learn to speak their lingo as it helps.

I think this bulletin is for other noises not what the guys are talking about here.

 

[Skylarking]

^ yeah, got that after I posted and realised OP has a manual
Also when OP later stated he’d been to the drag strip and track....

Drag strip and track work can make any car seem like a tired clapped out whore

But surely if Hyundai can warrant its i30n for track days, it’s not unreasonable to expect our expensive performance V8’s to handle such activities a little more elegantly that a junky whore

 

[eman1]

^ yeah, got that after I posted and realised OP has a manual
Also when OP later stated he’d been to the drag strip and track....

Drag strip and track work can make any car seem like a tired clapped out whore

But surely if Hyundai can warrant its i30n for track days, it’s not unreasonable to expect our expensive performance V8’s to handle such activities a little more elegantly that a junky whore

I hadn't replied in a while cause after having checked out by the performance shop and they said it is perfectly normal so I wouldn't say it couldn't handle the track or drags.

I also had a drive of the GF's WRX sti and its exactly the same, its more to do with a little bit of slack in the drive line which being heavier units in the VF and STI is more noticeable.

 

[Skylarking]

^ good to hear they are robust enough for some drag and track days

I’ve not played with diffs or drivelines but isn’t driveline slack an indication of pinion preload, uni-joint or spline wear issues? Easy enough to check. Isn’t thumps, especially metallic thumps something else and more concerning?

Guess we will find out soon enough

 

[eman1]

^ good to hear they are robust enough for some drag and track days

I’ve not played with diffs or drivelines but isn’t driveline slack an indication of pinion preload, uni-joint or spline wear issues? Easy enough to check. Isn’t thumps, especially metallic thumps something else and more concerning?

Guess we will find out soon enough

Can be, however from the opinions from shops I've had its well within spec so I guess I'm being too picky haha.