Hi Folks

Ok, so I am posting on this forum as I am assuming there are a heck of a lot more 405's on your roads than ours, so chances are good I can get feedback that hopefully helps me solve my concern..

So I recently purchase a 2014 L405 5.0SC Vogue SE with approx 32K Kilometers under her belt after my L322 was scrapped due to an unfortunate accident..

Beautiful, everything works as it should apart from the transfercase thump issue which will soon be resolved - LTB00906NAS4

But, here the odd.. If I drive her on a nice smooth freeway, take her to 140KPH and then decelerate, there is a notable rumble/drone as she slows down until speed gets to approx 120kph where all is silent again, almost like a V8 engine throttle off rumble, just its not the engine..

Its not engine noise, if I take her to 140 and then throttle off, select neutral and coast to below 120kph, the noise is there with either the motor engaged, or idling with the gearbox in neutral.

Its not loud, but its there, cant "feel" any vibration of sorts, just hear the noise.

We have a 5 year all-in JLR motorplan when vehicles are purchased new, which carries over to new owners when the vehicle is re-sold, she is still under JLR motorplan until June 2019, after which everything becomes my issue.

A few months back I had the Fattie in at JLR for this very issue, it was a rather painful 1 month to and fro affair, they replaced the following with new trying to resolve the issue:

1. Front Diff
2. Front propshaft
3. Front Sideshafts
4. Rear propshaft
5. Rear diff (open)

I can confirm the parts used where new as I inspected each item as being installed..

They even replaced the transfercase but then removed it and reused my original case as they said this issue is not transfercase related.

It still rumbles / drones in the speedband decelerating between 140-120kph..

She runs 22" turbines with original Conti tyres

They replaced my wheels with others "just in case" - no difference..

Very much doubt its wheel bearings..

They have pretty much thrown their hands in the air and given up, obviously this is no good for me, and I really understand that it is their obligation to continue with repair until the fault is fully resolved, but assuming they really cannot find the solution, has anyone noticed this phenomenon on their 405, is this just a normal operating noise that I should ignore??

Many thanks - All advice / feedback is truly appreciated!!