Could you put your model into your profile details please. It does help with answering

liamthedude wrote:

Is everyone in the agreement that it's the transfer box?

One thing to check is if the car has to be moving to get the vibration.
Try sitting in neutral and gently altering the revs up and down.
Is it engine (only) related?

Alternator Pulleys, Air Conditioning and other Engine Ancillaries can all cause noise/vibration.

Also, whilst driving, try Command Shift and other Modes as some will lock up the Torque Converter Clutch for longer. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

I had the exact same thing…shudder at 1800rpm which cleared after around 2100/2200rpm.
On a 2010 gs with 160k miles..
Took it to Suffolk transmissions in Sudbury and they diagnosed a worn torque converter.

Ended up agreeing to a new reconditioned auto gearbox supplied and fitted by them, as , given the mileage they couldn’t be sure other problems with solenoids etc would crop up later on and seeing as it’s a lot of labour to do it I went for it belt and braces.

Yes it was £3k but the car drives smoothly now ,it feels like new,and I’m enjoying it massively again.
I don’t plan on selling it either , just gonna keep
It till it expires!

Jimbowats describes it very well in his post last year, including the reason why the vibration occurs at this engine speed.
https://www.freel2.com/forum/post425332.html#425332

Sounds Expensive but Conclusive. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

I Like Chips wrote:

Could you put your model into your profile details please. It does help with answering

Simon J wrote:

liamthedude wrote:

Is everyone in the agreement that it's the transfer box?

I don’t think there’s any agreement that it’s the transfer box. The vibration (not really a shudder) is at around 1800 rpm, regardless of gear which suggests it can’t be on the output side of the gearbox - hence the suspicion lying with the torque converter.

liamthedude wrote:

I Like Chips wrote:

Could you put your model into your profile details please. It does help with answering

It should be done and in the system now. I will also say that I had a full service on the car last August, including a gearbox flush. It started juddering after this.