Squeal like a pig then warble like a turkey

Driving to work this morning my 300 TDi Auto started squealing like a stuck pig. I thought it was a belt slipping but when I got to work and put the car in neutral it would rev quite happily without a hint of a noise.
On the way home this evening the noise became much louder. I opened the window for a better idea and the noise was deafening. As soon as I let my foot off of the throttle the noise would disappear but then whilst coasting in gear it started to make a warbling noise like a turkey. If I quickly nocked it into neutral whilst coasting the turkey would shut up. So now I have a car that sounds like a stuck pig when in drive and a demented turkey whenever I let off of the throttle. As the piggy noise doesn't happen when the engine is revved in neutral and the turkey only makes itself known when coasting in drive do you think this could be a gearbox issue? I had a replacement Ashcroft auto box fitted about 5000 miles ago so I hope not but I can't see it being any of the drive belts like my googling suggest.
Anyone had a similar problem in the past?

Merry Christmas.

Paul

You're either going to be stuffed or saved by the bacon.

did you drive through a farm at any point today?

Or past a welsh hen-party?

Clutch release bearing?? or

Thanks guys. Yeah I know, at least I have Christmas dinner sorted.

bit big to get in the oven?

Sounds lick the torque converter I think the bands are slipping in it don't quote me on it

biolandy said:

bit big to get in the oven?

Click to expand...

Depends what speed you approach it at.

Wife went to the local LR Indy this morning and was told that the propshaft UJ at the gearbox end is stuffed. I will take a look for myself when I get home but good news if it is as she was quoted £15 for the part + 1 hours labour to do the job.
The gearbox is 3 months out of warranty so I hope it isn't gearbox related. I'll keep you posted.
I hope everyone has a great Christmas.