Over the last few weeks I’ve started to notice a whine during light to medium acceleration. It sounds like it’s from a central area so assume the transfer case. It started off fairly subtle but sounds like it’s getting slightly worse or maybe I’m focusing on it more. I hear it from about 15 mph, from then to about 60 mph it’s not that obvious. It gets to a higher more pronounce pitch at about 60 mph.

Of course I got on to the old Google and found a TSB relating the the L320 and micro wear on the chain. The symptoms sound similar to what I’m experiencing. Anyone had a whining TC before? If so I see a chain kit is available to replace the chain. I would like to try that option first, if possible, before going nuclear and shelling out either £4k on a reman or £5-6k on a new transfer case.

I’ll be trying to get booked into one of the Land Rover specialists in my area, hopefully MMP to get it diagnosed properly but think they are booked out quite far in advance. So just trying to get some information in the meantime.

Done a couple of props for a "central sounding" whine, rear diffs and wheel bearings are also fairly common...

Transfer box whine is very rare, even from the very early models. The only issues with the newer cases seem to be the infamous judder on turning

Funny you should mention it Mike. Took a small sample of all the oils an hour ago. Front diff and transfer case both look fine, golden with no glittery bits. Rear is pretty dark with some sparkles in it. All have only done around 4000 miles so would point towards rear diff. Took it for a drive with me in the back and the missus driving. Definitely sounds more rearward when not in the driver seat. I’ll give you a phone tomorrow about getting it booked it at some point.

I had the judder when turning but did a double oil change and calibration of the transfer case and it’s been ok since.

When I was under taking the oil sample there is grease being flung from the coupling just before the nut on the rear diff. Not sure if that’s maybe contributing also.