impreza humming noise under heavy braking!

[rb5230]

i had a humming noise when i used the brakes heavily which i thought would be cured with new discs and pads as the old ones were pretty knackered, anyway i replaced all the discs and pads on the whole car and got the brake fluid changed at the same time. the noise however never went. it is like a winding humming noise which of which the tone changes as the speed decreases, it only happens under heavy braking.

any ideas? thanks

[Rotary Madness]

Wheel bearings or CV joints? Could also be the gearbox but thatd be more of a whine noise.

[cptsideways]

ABS Pump

[Eggman]

Do your discs have grooves in them?

[Geordie boy]

Eggman said:

Do your discs have grooves in them?

Just about to ask this, my drilled discs do the same

[rb5230]

Geordie boy said:

Eggman said:

Do your discs have grooves in them?

Just about to ask this, my drilled discs do the same

they do have lots of grooves as did the ones i took off, its certainly not the gearbox, i wondered if it might be a wheel bearing although just under braking seems weird.

[Geordie boy]

The old ones probably had a build up of rust and brake dust in the grooves so the noise wouldn't of been as loud. If it has just come on since the new discs have been fitted then i'd dare say thats the cause.

[MrMoonyMan]

Grooved discs!

[rb5230]

ok cool, nice to know its normal, its quite loud though.