TD5 gear crunch when engine warm not cold

The oil change didn't solve my problem, it was gear box out and new synchro on the offending gear change and it was sorted, mind you cost me a few quid but I'll be running this landy for a long while yet so its needed to be sorted.

i had the same problem with my td5 disco 2 ! it crunched in 1st and 2nd for two years, now ive just had to change flywheel, clutch, clutch arm, thrustrace wos trashed ! bolted it up exspecting a nice box and it crunches in every gear, just droped it off to gearchange for reconning ! the choice is yours !!!!!!!!!!