Following this thread hope you worked out your problem. Here is what happened to me.. Hope the sharing helps others:
So, after spending a heap of time reading about Td5 "squealing" and having already changed auxiliary belt, tensioner and ACE pump (due to a bit of 'in-and-out' play in the pulley - which turned out to be a normal design tolerance) and it's still squealing!
So next line of thought was the dreaded exhaust manifold gasket and lo-and-behold snapped studs. Just a couple on port 1 and 5 - as expected.
Parts arrived (see this guys blog on part numbers and a good "how-to" TD5 Exhaust Manifold Change | Alex Threlfall's Blog) including longer Wurth studs and copper nuts (12mm socket M8's not 13mm socket M8's - get 'em from eBay!), some nice new left-hand drill bits and extractors - I was prepared for a fight!!!
But it only took 3 days of regular soaks in penetrating oil (I used "BreakAway- US brand available here in Spain" but I'm sure trusted WD40 does the same job) and with the drill on 'hammer' setting both broken studs popped straight out with no fuss !!!
The manifold was warped by about 1.75mm from front to back so that was skimmed by a local workshop and cost about 30 quid. So far so good. Oh, BTW this Td5 is not remapped soA
So to get the manifold off here are my tips:
1. use LOADS of penetrating oil, days in advance!
2. make sure you have a good socket set with all the 'bendy-bits'
3. get a deeper 12mm socket as the uprated Wurth studs are longer and they'll 'bottom out' on regular sockets. Also LandRover, in their almighty wisdom, have stamped their logo in relief on the manifold just in front of the bottom stud of port 2.. making it impossible to get a regular socket to line up OK.
4. Take the cover off the centrifugal oil filter and remove the filter. PLUG THE GAP WITH BOG ROLL OR SOMETHING - you don't want and nuts disappearing down the oil drain pipe!
5. A/C compressor needs to be unhooked but can be moved aside without needing to have it disconnected and de-gassed. Having moved it I found that one of the A/C pipes had been rubbing on the centrifugal oil drain pipe and had worn through the heat shielding. A plastic zip-tie held it out of harms way on re-assembly.
6. I don't know if this is recommended but I do it anyway - coat all bolt and stud threads with a bit of anti-sieze copper grease from Halfords... might help later on ;-)
Reassembly went like a dream. I did replace the turbo-side studs & gasket as well (not Wurth studs as they're too long for that side) and its a bit fiddly getting the bottom nut torqued up.. that's also where the patience is needed.
So I'm on a roll and everything goes great.
But, guess what, still squealing! WTF. Much less than before I must admit but I'm lost now for ideas. I'm gonna re-torque the manifold lugs tomorrow after taking it out on a good long drive. Refitting was done well... I promise! (re-did it to make sure).
So, any of you reading this have ideas or suggestions they're well-welcome. My only thought is settling in time for the newly machined manifold (which re-torquing might solve)... or, warped cylinder head (but I have none of the other typical symptoms for this). Apart from the (quieter) squealing this car is pretty much 100%!!!
Funny... I only give my car and my dog this level of attention ;-) my partner and family make do.....!
Hopefully this will help someone... and also help me....