Ford Falcon: Traction Control

Our BF Falcon has been back to our dealer five times since December 2008 with the same traction control issue. The first four occasions they either changed the sensor or re-set it, on the fifth occasion they said that Ford recommended they change the steering column. But they still cannot say 100 per cent that this will fix the problem, and now the warranty has expired they say they will not cover the cost and labour of the steering column replacement. I say that if the vehicle had not been wrongly diagnosed on the first four occasions this would have been rectified 18 months ago. Have you heard of any issues with the traction control system on the BF Falcon XR8? Would the steering column shaft cause the traction control to disable? What do you think my next cause of action should be?