Rattly, jingly chattering from underneath my 300tdi

My 1998 Disco 1 300tdi manual ES is making a very odd sound. It's been doing it for a few months now, on and off, but today it's constant. Hard to describe but over about 5-10mph there's a sort of chattering rattling sound, like a loose lightweight chain flapping against something hard. It's not engine speed dependent, doesn't go away with the clutch down or the transfer box in neutral or with the handbrake applied a little or the barkes applied a lot and is present in all gears. I doesn't happen at a standstill and sounds to be coming from the middle of the car, underneath - sort of transfer box-ish but it's very hard to pinpoint.

It just sounds like something loose, maybe a trashed bearing, and is usually accompanied by a sort of quiet "mooing" which comes and goes but the radio covers that bit up.

There's oil in all the right holes (and everywhere else, of course !) and the UJs feel tight and I can't sense any serious play in the prop splines.

Stumped! Any ideas, Disco team?

Could be exhaust , also check the mud shield on the front output flange of the transfer box, it's pressed on and can come loose .

Mud shield sounds promising. I'll take a look. Thanks.

Spot on. Just rattling around, unattached. Any way to get it back on without dismantling the prop?

Maybe you could use some sort of mastic or a tube of no more rattle ,

I took mine off then tapped around the hole to make it smaller, been okay since .

I take it that every LR dealer and specialist stocks tubes of "No More Rattle" in 6 or 12 packs !