Weird Noise

[BinaryMan]

Hi Guys!

This is my first post.

I recently bought a 2003 4runner v8. This has been a great SUV so far. Last night my wife noticed a ringing noise coming from the front of the SUV. After further investigation, it appears this noise is coming from the brakes but I don't know which wheel. The noise occurs when your are driving and does not seem to increase in pitch with faster speeds. The noise goes away when brake is applied.


Does anyone know what this problem is and how it can be solved without taking the SUV to the dealer?

Your input is very much appreciated.

 

[PlanetAlaska-]

Is it a constant noise, or is it intermittent?

 

[BinaryMan]

Is it a constant noise, or is it intermittent?

its fairly constant and soon as you touch the brake, it goes away.

 

[chaz]

heres a link that might help. see techwrenchs answer: http://www.toyota-4runner.org/4th-gen-t4rs/21058-floating-brake-pads.html

 

[chaz]

QUOTE:" the front calipers on these 4Runners do not use the anti-rattle clips between the pads and caliper like the rear system. The front calipers are a four piston setup, not a 'floating' caliper, like the rears which are a single piston caliper. Because the front caliper doesn't move from side to side, the pads are held in place with two pins which go into two alignment holes in each pad. The pads are allowed to float on these pins. There is a spring clip which attaches around the lower pin and is designed to keep the pads from rattling (Anti-rattle spring). The shims installed in between the pads and the caliper pistons are designed to stop brake pad squeal. If the anti-rattle clip is not installed, or installed incorrectly, it could allow the pads to rattle when the brakes are not applied."

 

[BinaryMan]

thank you for the link. Its been very useful.

 

[sr5hi]

its fairly constant and soon as you touch the brake, it goes away.

From what you describe you should have your front brake pads checked for wear. The disc brake pads usually have a small metal tab on them. As the pad material wears down, the tab rubs against the rotor causing that sound, it is an audible warning that your disc brake pads are getting low. When you apply the brakes the pad flexes a little causing the tab to pull away from the rotor and the sound stops. When you release the brake the pad returns to its normal shape and the tab again rubs against the rotor. Have it checked out, but don't wait too long, because if all the pad material wears away and you have metal to metal contact between the rotor and the disc brake pad you will ruin the rotor. You will then have spend more money to buy new rotors, instead of just replacing the disc brake pads.

 

[BinaryMan]

the front/rear brake pads were checked last weekend as part of annual safty inspection (required in VA). The inspector mentioned the rear pads barely passed and I should change them soon. I have the new pads on order. I'm going to change both f/r and hopefully that resolves the problem.