Vibration while in gear and stoped solved by replacing front driveshaft flex disc

[bmw540san]

As title states I had pretty significant vibration while in gear and sitting at the light for example. If I shifted to N or P the vibration would stop.
If you do search people mainly suggest motor mounts but I suspected someting else considering that vibration should be present the whole time if the motor mounts are bad.
Anyway, I did the careful insepction and found #1 to have hairline cracks:
https://www.realoem.com/bmw/enUS/sho...diagId=26_0175
When removed and compared to new part it apperas to have lost considerable amount of rigidity which it makes sense why it produced vibration.
During replacement I took the oportunity to inspect splines on the driveshaft and transfer case and found them have no wear whatsoever.
The flex disc was original at 129k miles and proximity to exhaust probably accelerated the wear.
So if you have these symptoms, it's worth checking it out.
When replacing make sure that arrows on flex disc point toward flanges and torque to 60NM.
You should replace the 6 bolts according to TIS but I didn't. They looked fine but I do understand they are exposed to stress. Having the lift in my garage I am under the car fairly often and I'll keep an eye on them.

[andrewwynn]

Often the TIS replacement is because the part is installed torque to yield but I don't recall that being the case. I reuse most suspension nuts and bolts that are not torqued anywhere near yield replacing only when they show wear.

CV wear can also cause that type of shake. Cured my wife's X5's jitters. In her case was amplified greatly by some stones on the stiffening plate.

[cn90]

Mine is a 2006 X5 3.0i 6spMT with 134K miles...

The last time I checked my flex discs (front and rear DS), they looked like 95% perfect with only very very minor surface cracks. I had to look very closely to see them.

However, I plan to overhaul the driveshafts between 135K-150K:
- New flex discs x 2
- New CSB (BMW brand)
- Regrease the Rear CV Joint and replace the paper gasket.

[Fifty150hs]

Originally Posted by bmw540san

As title states I had pretty significant vibration while in gear and sitting at the light for example. If I shifted to N or P the vibration would stop.
If you do search people mainly suggest motor mounts but I suspected someting else considering that vibration should be present the whole time if the motor mounts are bad.
Anyway, I did the careful insepction and found #1 to have hairline cracks:
https://www.realoem.com/bmw/enUS/sho...diagId=26_0175
When removed and compared to new part it apperas to have lost considerable amount of rigidity which it makes sense why it produced vibration.
During replacement I took the oportunity to inspect splines on the driveshaft and transfer case and found them have no wear whatsoever.
The flex disc was original at 129k miles and proximity to exhaust probably accelerated the wear.
So if you have these symptoms, it's worth checking it out.
When replacing make sure that arrows on flex disc point toward flanges and torque to 60NM.
You should replace the 6 bolts according to TIS but I didn't. They looked fine but I do understand they are exposed to stress. Having the lift in my garage I am under the car fairly often and I'll keep an eye on them.

I have that on mine. I've been trying to figure out for quite awhile what could be causing the vibration, only in gear. Now I've got a good idea. I have a list of things I'm working on between Christmas and New Years. Just added this.

[crystalworks]

I did a complete front/rear DS service a couple of years ago for PM. Still have vibe in gear at stop (with AC off mostly). Mine needs motor mounts.

[Overboost]

I would like to know more about this as well. I am having a loss of understanding how the flex disc can cause a vibration at a complete stand still since the flex disc is not even moving.

I replaced the engine mounts on my E46 and solved all the vibration issues I had at idle and I have the same vibration at idle on the X5 and always assumed it needed the engine mounts but I am open to an education here.

[EODguy]

Don't forget the transmission mount

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[crystalworks]

Originally Posted by EODguy

Don't forget the transmission mount

[EODguy]

Well it looked guilty....

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[andrewwynn]

Originally Posted by Overboost

I would like to know more about this as well. I am having a loss of understanding how the flex disc can cause a vibration at a complete stand still since the flex disc is not even moving.



I replaced the engine mounts on my E46 and solved all the vibration issues I had at idle and I have the same vibration at idle on the X5 and always assumed it needed the engine mounts but I am open to an education here.

Same reason that worn CV cause vibration or engine mounts. When engine is running and power train is engaged the individual hits of power load the system then briefly relax. When there is a worn part, the output shaft of the engine gets to twist things a little farther before the slop is removed.

Watch how much play is removed for example when a car is shifted from reverse to drive. It's the same play that is coming into action.

Often (likely always) when the guibo is the source it's loose bolts and you can punt on replacing by torquing them down.

The drive shafts are torsion springs and will store plenty of energy even at idle to push the transmission slightly backwards to loosen up the drive train ever so slightly to set up for the next power push and following jiggle.