I have the exact same problem on my 2003 HSE.. Also on the rear right hand.. I'm thinking its the rubber bushing in the lower arm..
Curiuous whats the outcome on your car is gonna be!
Keep us posted!

it was not the rubber bushing but the lower ower ball joints ("rotule inférieure").
The upper one was changed while they were at it, then alignment. l=Oo\________/oO=l l:OolΞΞΞΞΞΞΞloO:l

Current
RANGE ROVER Vogue 4.4L SDV8 - 2013 - Indus Silver, on Almond.
RANGE ROVER Vogue 4.4L V8 - 2002 - ex-2003 G4 Challenge Event Vehicle, Stage 3: Australia
RANGE ROVER HSE 4.4L V8 - 2004 - one-of-one Overfinch
RANGE ROVER P38a 4.0L V8 - 1999 - ex-2000 TReK Event Vehicle: South Africa

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RANGE ROVER Vogue 4.4L TDV8 - 2012 - RANGE ROVER 3.6L TDV8 x3 - RANGE ROVER Td6 x1 - RANGE ROVER Classic 3.5L V8 x1

I have a RR Vogue 2003 L332 and I had the 'creaking' noise from the rear too. I greased all the joints but it only helped for 30 minutes. In the end I took it to my local garage who only do Land Rovers.

The day before I had it booked in I had an awful creak start on the front, much louder than the rear.

Took it to the garage and had all four knuckle bushes changed, these are the ones which have the wheel hub attached to.

When I collected the car I was informed that the noise from the front was cured by torquing up all the suspension joints as none of the bushes had gone.

The replacement of the bushes was £495. The torquing was free. This was genuine RR parts.

The car drives like it was new.

I am good at mechanics but really couldn't be bothered with this task. Special tools, seized bolts, freezing cold and massive amounts of Elbow Grease and the thought that it may go wrong put me off!

I also had Hunter four wheel alignment done which cost £80. Well worth it.