Land Rover Repair: Discovery 1993 Steering Vibration and feed back, wheel bearings, suspension bushings

Question
When i get to about 70/80kmh if/when I hit a bump the steering wheel goes crazy like the wheels are not balanced. It is so bad that it will move you around on the road and you have to immediately slow down or risk an accident. I have replaced the steering dampner twice, replaced the tie rod ends, checked the wheel bearings and have rebalanced the wheels but still the problem persists. Is there something I'm missing?

Answer
Something has to be loose or set wrong.  You can see all the suspension bushings but here are some possibilities you can't see:

1) Even the tiniest play in steering linkage ball joints will set this off
2) Check tire balance
3) Check swivel ball preload
4) Check caster, especially if the truck is lifted.  
5) Check toe - too much toe in will cause instability

Good luck with it

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