300 tdi jumps out of gear

I have done a search first but didn't find much to relate to,so hoping might get some joy here. When in second gear at low revs sometime our disco will jump out second gear. It does it most when going over a bump,or down the farm track to my mother-in-laws house. It does have the second gear crunch also. It does have some forward backward movement in the rear axle due to the rear radius front bushes been shot. The bushes and rear shocks are being replace this weekend. Does anybody have an idea as to why its doing it only in second gear
many thanks in advance
alex

Worn bulk rings on 2nd gear I would expect.

sounds dear then. lol

Depends if you want to swap the whole box or just strip and repair the box.

i would probably swap the box if it came to it,its not all the time at the minute but i know it will get worse. Just had a box of goodies in the post today so i can start my repairs this weekend. Should make the back end alittle stiffer i hope. Next up some new tyres