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does it do it while moving or just braking.
can you spin the wheel and here it
is the exhaust tight and not hiting anything
DATE: Aug. 19, 2002
A cyclic swoosh, squawk, squeak or grunt sound from the rear of the vehicle may be heard during medium to light brake application on vehicles equipped with rear drum brakes. The sound will be related to the speed at which the tire/wheel turns (one sound per revolution of the tire/wheel).
If the vehicle operator describes the subject Symptom/Condition, test drive the vehicle to verify. Perform the Repair Procedure if the symptom/condition is experienced during the test drive.
have also seen if lube not put where shoes touch on backing plate
trying to get close since you already replaced everything.
please dont accept untill your satisfied
That is great, but I did in fact lube the pistons in the wheel cylinders. In fact, I greased everything that I could grease to ensure I had no other sounds to worry about. Like greasing the back plate where the shoes rub against it as well as the self adjusters and so on. Don't worry, I did not grease the shoes or the drum and cleaned everything with brake cleaner. Again, this happened with the old wheel cylinder as well and it may have actually been fine anyway. Also, the knocling is only coming from one side. I cannot say that the wheel cylinders are the issue here. What else do you have?
the only thing else i can think of backplate loose, shock movement inside tube which is normaly just 1 knock.
wheel bearing which normal constant growling noise.
rubber bushings in springs.
HelloCustomerand thanks for choosing JustAnswer.com!
I see you are in need of further opinions about your issue.
Honestly, doesn't sound like it's the brakes causing this, as you would probably have issues parking it on a hill with the handbrake. I suggest inspecting bushings, either shocks or suspension components bushings. When you brake you are mainly using your front brakes. The rears only come on slighly to help stop the back end from overtaking you. Also when you brake, all the weight of the car goes forward putting less pressure on the rear suspension. Try tapping the brakes and see if you get repeated knocking as the weight shifts back and forth making your suspension lift and lower repeatedly at the back. See if your shocks are leaking or if any of the bushings are rotten, worn or just gone. Also bounce the car up and down while the assistant is inspecting the shocks/suspension to help him/her pin point where the problem may lie. Let me know how the inspected parts look and I will follow up.
I just finished checking the bushings and suspension and found no knocking noise. Some bushings are looking old but still functioning. Shocks are not leaking, and bouncing does not generate the knocking sound. Again, the knocking is clearly coming from the passenger side rear wheel. Still only when applying the brakes and rolling down the road. Even when roadway is very smooth (new parking lot nearby). I tested the handbrake and it does hold. Please check with someone to see if an out-of-round or warped drum could be the cause before I go ask for a new one.
A warped drum could indeed cause it but it is just highly unlikely that both the old and the new drum would have both been warped.