Renault Laguna steering wheel wobble

TRY SWAPPING FRONT AND REAR WHEELS OVER TO ELIMINATE THAT, POSSIBLE IT COULD BE A SEVEER DEFORMITY OF THE BRAKE DISC ON THE LEFT HAND WHEEL

Yes it could be what the chief has said,you could have a buckled wheel,or some of your steel bands snapped in your tier,causing a bulge in your tier causing it to wobble,or your tiers need balancing,tiers that have not been balanced,or have lost a balance weight,cause your steering wheel to wobble and vibrait at certain speeds,your tracking could be way out,you could know all this,just in case ,has it just happend,can you think of anything that could have caused it ,have you hit a bad pot hole,hit the curb hard.???

Yep, have gone over potholes etc, normal British roads!!!! I haven't done anything to the wheels, had a back one changed a couple of months ago because of a puncture, but thats it, can't remember if the problem was there or not then! The garage has had the car for 5 weeks trying various things but still no solution! Thanks for your help so far people.