Car Veers Left N Right When Braking At High Speeds

[SargeRX8]

The other day I was on the M4. Was cruising at about 100 - 110km/hr. Had to suddenly break hard and the car does not stay straight when braking. The car must be braking harder on one side or something. What should I do? How should I diagnose and fix this issue? The brakes were fully rebuilt at 100000km. The car is now at 118000km. Could the brake pads be worn? Could the brake system need bleeding?

Slowing down slowly is fine. Slowing down hard at speeds like 80km/h the car slows fine. Its just greater speeds.

[R32 TT]

Possibly alignment is out... Worn bushes in the suspension deforming under hard braking?

[SargeRX8]

Hmm it could be the alignment. I had the wheels balanced a while back and they checked the alignment and it was a teeny bit off but they suggested not to pay for them to recalibrate it over that. Recently, though, I had the old gel filled castor bushes changed to solid aluminium castor rods.

It can't be the suspension as I suspected I had a suspension issue in the past but had it checked out by pedders. They done a full inspection and said my suspension is in top notch condition and very firm.

How often would I need to change the brake pads?

[R32 TT]

My gut feel is that if it were brakes you would feel it at normal speeds. The fact you are only experiencing it under hard braking makes me think it's wheel movement somehow... Ie either suspension or tyre deformation?

Toe out will sometimes mAke the car feel twitchy under hard brakes also..

[PUDZ 32R]

im going with toe out or incorrect alignment in another way.

from what i understand you had your suspension checked and then replaced the bushes afterwards? if thats the case it could have moved.