have i just lost my reverse gear?

[rossbarry1]

I was just rocking my car back and forth to identify a knocking noise when my gearbox jumped out of reverse and started making a grinding noise (like changing gear without the clutch!) now when i put the car into revere and lift the clutch sometimes it bites but only for a tiny bit then it crunches, and other times it doesnt bite at all. Its a mk2 golf gti 8v '89. Any help or advice would be great as i dont fancy paying out for another new gearbox in 3 months!

Thanks

[Andy!]

Is there oil in the box?

[Wayne]

Has the clutch failed. 

[rossbarry1]

not sure about oil, there should be it was only put on and filled up, clutch cant have failed because i have drive in all other gears.

[Andy!]

I asked about oil because your problem is similar to what was happening to the box on my previous GIT before the box blew up.