Hello, im at my wits end and i stumbled accross this great website offering help and advice and boy, do i need some!

I recently bought a 1999 mazda 323f 1.8 16v 5 door hatch, its the newer shape, anyway, although when i bought it, it came with 12months mot and history with peace of mind and knowing mazda generally had good reputation ect ect, anyway long story short, it developed this knock knock sound which seems to be coming from front of car only when i "BRAKE" it seems to knock on rotation which means faster i am driving to come to brake the knocking sounds faster, when i slow down it follows suit (?) if you know what i mean.

yesterday i took it to my local garage and said all my pads were worn all round as i got discs all round with abs ect i took there advice and they did the work, costing me £100 for the privalige, and you guessed it, it still knocks upon braking so instead of forking out more money, any help or advice what problem could be? i thought ball joint but that wont explain why its constant knock when i only brake and stops when i cruise, anyway thanks for any postings on this topic!!
gary

Hi Gary,

Knocking both before and after new brake parts does suggest it's NOT those parts that are now new. By nature, describing a noise is tricky but I'll say that a wheel bearing is a possibility. Usually those make more of a rough road feel but a cracked race could be the sound you hear. Certainly rule out all safety items such as tie rod ends, ball joints, CV joints - anything to do with suspension or that rotates. It could be a tire, rim or hubcap too. If that's suspect - rotate wheels and see if noise follows a wheel.

Bearing race issues can be elusive. See pic of a generic flawed one..........




OK: You no doubt have a sealed bearing so can't just see this. Another basic pic of a bearing shows inner and outer races ....



OK: It's rare but the flaw could be such that the load of the vehicle's weight isn't right on the flaw until forces change when braking.

As said - a bit rare to fail this way but they can. Will take careful inspection of suspect wheel AND the other side as well as a noise can transfer and make you swear it's one one side but is generated from the other - don't ask how that can do that??

Know this much - If a worn, failed part it won't get better and could cause a big surprise or quick failure so it has to be resolved asap.

Good luck with the fix and please tell us what was found,

T
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Tom Greenleaf - MetroWest, Boston

Thanks for the posts re my braking problem, i have just put the car in another garage and i am awaiting there review of the situation.
I will let you know what the mechanics say.
cheers.

From across the pond as they say - good luck with an accurate diagnosis. The cracked race is tough as said to be certain of. Allow trusted techs to drive it and hear and feel this for them selves.

Hey - IMO - if that's what is found it's nobody's fault just sh*t luck,

T
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Tom Greenleaf - MetroWest, Boston