When the window is down I can hear an irregular light rattle like a light metal object is being dragged along the road on a bit of string so it’s not a scraping sound. Seems to come from the rear OS and only when going straight or in a left turn at 30-50 mph ( wind noise kills it after 50). Had a look around poked and hit a few things but couldn’t see anything apart from if road clippings hit the underside of the air reservoir it may make the same noise. Doesn’t sound mechanically serious but needs investigation I think. 2012 TDV8 Vogue (L322)

Heat shields rattling after aluminum hss rotted through at the bolt points

Probably

As dingg1 says - The underbody heatshields would be my first point of call, they corrode at the fixings and become loose.

Another possibility could be a loose baffle in the exhaust - give each of the silencer boxes a thump with the side of a closed fist and listen for any rattles.

Next would be to check the handbrake shoe retaining clips haven't pulled through the backplate and there are some bits jingling away in the handbrake drum. Although TBH, this normally produces more of a grating sound as the bits get jammed between the drum and the handbrake shoes.

There's always a chance of it being gravel trapped between the disc and the backplate, but again this would give more of a grating sound, as I'm sure you're aware.

Hope you find the cause!

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
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Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

JayGee wrote:

When the window is down I can hear an irregular light rattle like a light metal object is being dragged along the road on a bit of string so it’s not a scraping sound. Seems to come from the rear OS and only when going straight or in a left turn at 30-50 mph ( wind noise kills it after 50). Had a look around poked and hit a few things but couldn’t see anything apart from if road clippings hit the underside of the air reservoir it may make the same noise. Doesn’t sound mechanically serious but needs investigation I think.

Turned out to be the front OS brake shield which yesterday completely detatched itself. Quick fix with some repair washers and all is quiet again. 2012 TDV8 Vogue (L322)