Hi, Im having trouble trying to find the size of the hub nut on my Ducato 3.0 2008 ive read so many different threads with posts that have different nut sizes from what I can gather the two that stand out most is 41mm which seems an odd size and 50 which to me mine looks smaller than.
I have a 36mm which is to small but not by a huge margin I don't really want to have to be going back and forward trying to source the right size socket.

My second problem is the tie rod end ball joints. now from what I am reading you back off the locking nut but on my van there does not seem to be a locking nut that is separate to the end there is a 24mm nut but it is part of the joint end there is however a separate nut in the boxes that new tie rod ends came in I have tried putting mole grips on the tie rod and the 24mm spanner on the tie rod end but it wont budge any suggestions please. Thanks Kenny

Drop into your local tool shop or go on ebay and get a cheap pair of vernier calipers. You will use them a lot as they are so fast at measuring internal and external diameters of nuts, bolts, etc.
The garage next door to my business does a lot of tracking, which involves freeing off track rod ends. They use big mole grips to hold the track rod and heat - lots of it! I reckon they use more oxyacetylene on track rod ends than anything else. The heat also forces the releasing oil they use up the threads of the track rod end (as the oil boils). Give it a go with a butane blowlamp, but if no good, get a good tyre shop or small garage to free them off for you. Even on cars just a few years old, the track rod ends can be siezed very solid.

41mm is a standard Metric spanner size. The next one up is 46 mm.

Check the size by measuring the nut across the flats. A tape measure or rule will do.

The next standard size down is 36 mm.

Nice 1 lads got the track rods off with some heat there was a separate nut. The nut was just welded to the track rod end. Turns out the Hub nut is a 46mm bit of a mental size but it came aff nae botha.