ok so i've just inherited this van a 2002 ducato 2.8jtd,
i have an issue i just can't fully figure out so if anyone can help please please do!!

right so, the van will go into 1st and pull away no bother, it then gets hard to get into 2nd, it will sometimes crunch, going into 3rd is always a crunch, into 4th is ok, but into 5th then more crunching.

i have tried double clutching, matching revs and it doesn't help.

after a day of searching internet i have come across some possibilities, gearbox knackered, i hope not, low oil in gearbox (i changed the oil today and it was fairly clean but tiny metal fragments on drain plug) i'm guessing this is from the grinding.

the clutch seems ok but i'm not 100% on that and the linkages from gear stick to gearbox also look ok as far as my very amature eye can see.

synchromesh? can this be a diy job? could it be the cluch going or gone?

if you have any clues please let me know as i'm pulling my hair out!!

thanks

There are a couple of things to go through first before you get into gearbox changing.
The clutch may well be dragging, so bleed the clutch hydraulic system. Then, there is the gearbox cable pivot on top of the gearbox, cleverly positioned under the water drain pipe from the scuttle, so the pivot seizes up. See:
https://www.fiatforum.com/ducato/296026-ducato-2006-clutch-gearbox-issues.html