Hi All,
Recently bought a 2008 L322 tdv8 3.6, get a bad judder, if I give it more throttle it pulls through it, also the rev counter moves up and down approx 400rpm and it sounds like I'm dabbing the throttle is the best way to describe it, from memory is this a possible torque convertor problem?

I have a very reasonable quote to rebuild it with a lifetime warranty so only major hassle would be dropping the box off to remove it to be sent away, no warning lights but would not expect any if its a TC fault, am I barking up the right tree?

This is a Torque Converter symptom as you already summised. Whilst the box is of you should also change the mechatronic block seals, fit a new sump/filter and refill with new oil when fitting 👍

You could look at putting it in command shift to see if that reduces the problem - if I recall correctly the TC should lock up sooner in command shift / sports mode, although that did make a noticeable improvement on mine as the TC was completely shot.

Thanks for your reply, glad to see my brain can still remember some things lol, it does seem better in sports mode, do think the box revs the engine instead of using the available torque to much, but after speaker to a remap guy he says they can be improved with some tweeking, better get the TC fixed first before I consider a remap, only trying to get max mpg, she has enough power lol, better dust off them spanners and get busy

There's some more info on this thread that may be of interest to you.
https://www.fullfatrr.com/forum/topic68557.html

The TC isn't toooo bad of a job, although I fitted the TC to the engine and then lifted the gearbox up to that, which of course I didn't realise there was an alignment feature inside the TC and spent ages trying to get the gearbox home before dropping it again and seeing my problem.

Yes the remap (&gearbox flash) would improve driveability, but you need to resolve the issue first. One annoying thing is there are a multitude or Torque Converters, so when replacing mine the chap narrowed it down to 2 possibilities on the phone, but wanted to see it in person before giving me a replacement. Luckily he had this on the shelf so it was walk in walk out.

Last thing to note is the O-Rings on the gearbox cooler lines. Be sure to replace them with Viton / OEM rings (because they're a stupid size) and be careful not to rip them on reinsertion of the pipe, I snagged one and developed a slow leak after the box was hot.