Double post, sorry.

With 17 years experiance as a tyre fitter your shudder under brakes leans towards rotors being warped. Not knowing how much ware is on the rotors you could get them machined for roughly $40 each or use the excuse for a rotor upgrade at not much more than standard replacement cost.

Is there any clunk in the steering when you quickly turn the steering wheel left to right. If so do you see a jolt on the wheels when doin this? If you do and have some car ramps handy put the front car up on them and cut the straps to the inner of the steering rack boots. Peel back the boots and start car and have a mate turn the steering wheel back and forth and check for play in the ball joints of the steering rack (rack ends) if they are worn it can cause bouncing in the steering wheel and the car to wander.

Just reading through the thread and just about everything is covered bar two possibilities I can think of. There is a small possibility that you could have a seperated tyre on the car that is running out of round as speed increases or maybe you could have a buckled rim.

but im pretty sure he had the wheels balanced.. therefore it would show up then

but im pretty sure he had the wheels balanced.. therefore it would show up then[/quote]

depends on the balance machine, most modern balance machines only spin the wheel slow so a bent or buckled rim would be found if it was looked for but a seperated tyre can look good until it reaches a spin rpm equilivent to around 80kph then you can see the tread lifting from the case of the tyre.