An update for anyone interested. The car was in at dealership today re clunking towbar, service dept confirmed they had received info from Land Rover about known problems and replacement part now on order. Hope to have it fitted early next week.
My thanks to all who posted information regarding this, it has beeen very helpful.

Robert

8 months down the line with the 'new and improved' locking system and about 1000 miles of holding tractors up , and the clunking has started again. Not noticeable with the van on the back yet but you can feel a slight knock when fitting the towball into place and swinging on it by hand.
See what happens in France Saturday onwards for two weeks

sure thats not the sound of tractors ramming you from behind. captain slow ? At work
At home

"I can't always believe facts I read on the web" - Charles Dickens

winner by default of the tractor vs caravan race

mcphersonstrut wrote:

8 months down the line the clunking has started again. Not noticeable with the van on the back yet but you can feel a slight knock when fitting the towball into place and swinging on it by hand.

Ditto

Update on the Detachable Brink Towbar.
I have just had word back that a new design of the Receptor and Towhook has been released, this has only been released in June of this year so if like me you had yours changed prior to June it will be the same as the one you had problems with and will like mine and others fail again. Brink it seems realised there was a problem but issued replacement units identical to the original whilst they modified it.

That's great thanks for the research + good info, seems like I need to pay a visit to the local LR dealers. However, the information will be scetchy at best for one forum member who will want Brink serial numbers of introduction, manufacturing dates, fabricators nationality, welders middle name and sales managers daughters date of birth as a minimum, otherwise they'll just think it's a joke

Thanks to everyone for all useful info in this thread. My LR badged Brinkmatic makes awful clunk with white box attached on bumpy roads. Asked local LR dealer about Service Bulletin but he was reluctant to admit that Service Bulletins even existed! Visited another who was really helpful and checked my towbar - it was worse than I thought and could be moved visibly by hand. He contacted LR and confirmed fix available under warranty (as long as FL2 is under 3 years old, if fitted at new or towbar is under 1 year old and LR fitted). Mine fitted 10 months so should be OK.
Part Number quoted as VPLFT0010. Waiting for availability and fitting. Fix is said to be a meatier swan-neck attachment mechanism - more surface area in contact.

I think Brink are a little more concerned by this as my Brink Bar is coming up 2 years old and Brink never hesitated in getting it replaced after I had given them the relevant details, it was replaced a last week, parts took less than 48 hours to be sent after they were given the details. Side by side no visual differences between the old and the new just tightened tolerances.

If anyone else has a problem with the Brink bar I wouldn't rush out and get the modified one just yet, I have done 200 miles with the Trailer on and the clonking is back and if I get a good hold on the ball there is amout a millimetre of play in it already.

 At work
At home

"I can't always believe facts I read on the web" - Charles Dickens

winner by default of the tractor vs caravan race

Update on the Brink Bar,
This is what Brink have said when I spoke to them earlier, the latest ball and receiver released in June this year should have on the top of the ball on the second line the numbers 215 this is supposed to be the latest modified one. But I have just had another one fitted (the second in a month) and both had 215 stamped on the top of the ball.

There seems to be a little confusion though but I will let Mcphursonstrut add to this as I know he has just had his replaced.

I have just had mine replaced 'again' by LR and it has a 311 ref on it....(was 215 )

Exactly, as I said Confusion but Brink swear that 215 is the latest one and no way was 215 out before June and that 311 is the old one

Why don't we just give ''you know who '' a gallon of petrol and a box of matches as he'd love to start a fire with this one....

Have had the swan-neck replaced (under warranty) last week but not yet had the 1400kg swinging off the back. Mine is marked 311 also, so left with two thoughts; LR are fobbing us off with existing suspect stock or Brink/Thule are fibbing about the correct marking. Wonder where my money would be placed. Just received e-mail from dealer carrying out last service begging glowing report for potential LR follow-up survey so have asked them for definitive answer on fix. At least I will have something in writing to hurl on to someones desk should it fail again.