I have the same problem on my 06 LR3. Don't know what they are talking about re-lubing... have you had any luck with it?

 

So what I understood from the dealer regarding the re-lubing what that the "flap" which opens and closes the air exchange can get slightly dried out and warped, so they use a silicone based product that allows the vent to open and close without as much noise. It was a fairly extensive project from what I understand. (Clearly I am no mechanic.) Mine was most noticeable when I turned on & off the climate control, so as soon as I turned on the vehicle, a 'fart' sound came from next to the passenger in the dash.

 

I am having the same "fart" sound coming from under the glove box. Happens when A/C or heater is turned on or off.
I heard it may be a vent door squeaking as it cycles?

I know it has been addressed before, but I never heard how it is fixed?