annoying shakes...

Morning boys & girls,
We 've just come back from our holidays in France and on the way home we were tanking our Disco (Mark 1, 1998, 300 TDI) in order to reach the ferry in time. When we hit around 70 mph the Disco started doing the shakes but when we managed 80 mph the shakes seemed to stop. Any ideas as why this happens and what I can do about it?

Cheers
Alex

could be many things.. start with checking yer steering for worn balljoints etc. then your suspension for any slackness.
the most likey cause will be wheel balance. but as you can check the others for free then you're aswell to check them first. if you don't find any wear or slackness then get the wheels balanced

check your prop shafts for play in the joints (sideways movement, not turning movement)