Knocking when braking ?

[gta_knight]

Hey guys, This knock has been there for a bit, over the last week i have replaced the brake discs and pads, that didnt help but i wasnt expecting it too they just needed done anyway. What i thought it could be was the balljoint after inspection, i jacked the car up and there was loads of movement so i thought maybe it was rattling around under braking, so ive just had them replaced, but when i took the car out and stepped on the brake....KNOCK KNOCK KNOCK KNOCK. Ive checked all the steerings/suspension bits and just about everything else under the car and nothing seems to be loose. If i brake lightly, the knock is fairly quiet, but if i slam the brakes on the knocking is very loud and you can feel the car shaking about when coming to a stop. definitly sounds like its coming from the front. A friend of mine suggested it might actually be air in the system and i should bleed my brakes, i would have never of thought of that ?

[always tinkerin]

Remove and inspect front wheel bearings.

Check to see if new brake pads fit loosely on calipers...even 1/4" rotational movement of the pad on calipers will make knocking noise when stopping. (ran into this last week-Autozone gold pads)

[gta_knight]

well do i feel stupid, i was convinced it was coming from the front and the other day i thought id test something, so i pulled the handbrake up a bit while going down the road and...KNOCK KNOCK KNOCK...

so i got the drums off and there was a fair bit of crap in both sides, so i blasted it out with the air gun, however my right hand side drum has a big groove scorn into it which corresponds onto the shoes. Both sides need new shoes looking at them, so i think i'll get new shoes, drums and pistons and get it all sorted out