A couple of weeks ago my 300tdi Disco started making a rythmic squeeking noise along with a vibration which seemed to be in tune with the road speed.

Aha! I thought. U/J's. Put the Disco up on my mates ramp. (he's an MOT tester). No play in any of the U/J's but we greased them all anyway.

The squeeking disappered, and the vibration got noticably better. I put the remaining vibration down to mud and rubbish stuck around the wheels (my Disco leads a very hard life).

2 or 3 days later I had to recover my mates Audi Q7 from a really muddy field, and in doing so used diff-lock and a bootfull of revs (probably not the best of ideas).

Anyway, on the way home I noticed a the squeeking noise had returned, but sounded slightly different, and there is a noticable clunk from the drive-train when changing gear.

I've noticed over the past week or so that the squeeking noise is only there when the drive-train is under load. The noise dissappears when on over-run.
Also the noise a clunking seems to be coming from the drivers-side front wheel.

Sooo. Have I knackered a half-shaft whilst recovering my mate, or have I got a failing CV?

Any suggestions as to checks i can do to diagnose this better would be helpfull.

have you got enough oil/grease in your hubs?? check no stones behind the backing plate