Wiper drift at high speed

[paul504]

Wiper on my '98 V8 works fine - returns to park position etc however go over 85 and the thing has a mind of it's own. Wind force moves it round its arc of travel by around 250mm at the outer tip. My freindly garage man said it happens with all of them - As the car has 1 month's warranty left, is he giving me the fob off as I know it's a bugger to get to / change the motor etc.