I've searched all of the forums as well as YouTube for a diagnosis for my problem but I'm really struggling.

I have a high mileage (180,000) 2007 Mk4 Mondeo which has always had the common turbo whine but today it has developed into something which sounds much more serious.

The whistle / whine is ridiculous and is directly linked to the turbo spooling up. It sounds like a really noisy supercharger on full chat!

I checked the oil and it barely registered on the dipstick. I've topped this up but the noise is still there.

All of the pipes (which I can see) are rigid and there are no splits to the inter-cooler that I can see. 

I can't even see where the turbo is located so I'm looking for a thread or 'how to' guide which will allow me to remove and assess the damage.

Should I be looking for anything else in your experience?

Your help is much appreciated. I am mechanically competent and have a good selection of tools available so due to the age and mileage, I'd like to have a pop at this myself. 

I had the same issue with my car (petrol 240ps) and it turned out to be the impeller in the turbo had gone (it moved up/down and you could pull/push it backward and forwards) and the car was eating oil and whooshing loudly (embarrassing) with a smoking gun exhaust.

The mechanic replaced 3ltrs of oil (it takes 5.5ltr) and then it continued to drink the stuff. Compression test carried out to check Pistons and rings (OK) then engine stripped to physically check the turbo - the culprit.

He did say on the diesels it's possible to reach the impeller with your fingers without stripping down the engine, but not possible on the petrol. 

On the petrol the turbo is part of the manifold and is located to the top and rear of the engine. I've no idea of the diesel is the same. 

Hopefully this may be of some help?