Hi I have a 95 M Astra 1.7 diesel and last week 5th gear disappeared, it's like it's blocked off. It has come back now and again - for a few hours and then goes again. The other gears all seem fine. There's nothing that I can see visibly broken, just wondered if this was a weird or a common fault. Been scouting round the internet and haven't found anyone with exactly the same problem so guessing a bit weird. Cheers.