hello and welcome mate,,,,,,,,if its crunchin o dear......but if its screechin probly bearins if its a iia box the front layshaft bearing usually goes first and the box lets out a screechin noise,,ie bearin cage broken up and all balls fall together ,jam and screech,,,easy fix AFTER you get the g,box out bell housin off you can see the bearing collapsed mind u its a pig to get out without taking the box apart but it can be done persevere...ive done it,,,or rebuild the whole box with new bearings @ £100 for a bearin kit.....series ii and iia boxes are usually very strong but unsofisticated.......siii boxes are similar but slightly weaker wehter they suffer from the same things im not sure but i would think so.....hope this is helps dave .......welcome by the way,,,...
