Grinding noise front end passenger side

Tiny
REGINA MATTEAU
  • MEMBER
  • 2004 SATURN VUE
  • 3.6L
  • AWD
  • AUTOMATIC
  • 173,000 MILES
I recently bought the car listed above it a v6 awd. I replaced the tires, wheel bearing and hub and front passenger caliper. Now there is a grinding noise coming from that side I believe. When you go above forty miles it is not there but when slowing down to about ten to twenty miles it is there. Just wondering what it can be.
Do you
have the same problem?
Yes
No
Thursday, April 13th, 2017 AT 4:38 PM

5 Replies

Tiny
CARADIODOC
  • EXPERT
The most logical suspect is worn brake pads. One potential clue is if the noise changes when the brakes are applied lightly.

There can also be rust buildup on the brake rotors if the vehicle sat for a while. That will usually wear off within a few miles, but heavy rust can take longer.

Normally we give the front brakes a quick peek when we have the wheels off, and we cannot help but to see the amount of pad wear when replacing a bearing assembly. If the pads were fine, the next suspect is improper installation procedures of the new bearing. There must never be any vehicle weight placed on the new bearing until the axle nut is tightened to specs. Some people set the tire on the ground to keep the axle from spinning so they can tighten that nut. At that point the damage has been done. The new bearing will instantly become noisy and sound like the buzz of an airplane engine.
Was this
answer
helpful?
Yes
No
Thursday, April 13th, 2017 AT 5:25 PM
Tiny
REGINA MATTEAU
  • MEMBER
It does not sound like that. It is just a grinding noise when driving it slow when going fast it stops. Will have to check pads and rotors. The drive side rotor is smooth but the passenger side feels like grooves are in it now. Could that be the issue?
Was this
answer
helpful?
Yes
No
Thursday, April 13th, 2017 AT 5:47 PM
Tiny
CARADIODOC
  • EXPERT
Grooves do not cause noise. If the linings on the pads are worn down, the metal backing plates and/or the rivets, when used, will cause grooves, and the grinding noise. Very often the pads can be seen through the wheels without having to remove them.
Was this
answer
helpful?
Yes
No
Thursday, April 13th, 2017 AT 7:43 PM
Tiny
REGINA MATTEAU
  • MEMBER
Ok so heres where I am as of now. Brake pads and rotors have been replaced. New caliper was put on. When trying to bleed the breaks no fluid comes out breaks do not grip at all when hooking line to caliper. When line off fluid comes out any ideas?
Was this
answer
helpful?
Yes
No
Friday, April 14th, 2017 AT 6:36 PM
Tiny
CARADIODOC
  • EXPERT
I'd have to see that fluid flow to make a diagnosis. If you only get fluid with the hose disconnected, I suspect that fluid is just running out of the line as air goes in.

A failure to get fluid flow is a common problem on GM front-wheel-drive vehicles. There is a valve in the master cylinder that trips when unequal pressures build up in the two parts of the hydraulic system. That stops the loss of fluid when there's a leak, but it will also trip for other reasons. In this case, the valve likely tripped because of the new caliper. The piston in it has to be run out until the pads contact the rotor. That is the self-adjusting feature of all disc brakes.

This vehicle will have a split-diagonal system that puts the left front and right rear wheels on the same circuit. When pumping the brake pedal to run the piston out, no fluid pressure will build up in that part of the system, and that's when the valve will trip. From that point on, no more fluid will flow from the master cylinder to those two wheels. This can be avoided by never pushing the brake pedal past half way to the floor. Professionals never push the pedal over half way on any vehicle more than about a year old to prevent causing damage to the master cylinder. Given the age of your vehicle, this is another problem you might still run into. Crud and corrosion build up in the lower halves of the bores where the pistons don't normally travel. Pushing the pedal over half way runs the rubber lip seals over that crud and can rip them. That results in a slowly-sinking brake pedal, and that often doesn't show up until two or three days later.

The only way I have ever found to reset the valve in the master cylinder is to loosen the cap on the reservoir, open the bleeder screw on only one of the wheels that isn't flowing any fluid, then give it a quick, short burst of compressed air. It just takes a fraction of a second to reset the valve. You want to avoid sending air into the line any further than necessary. That just makes it harder to bleed.

Once the valve is reset, just let the caliper gravity-bleed. It will only take a minute or two. Once the fluid is flowing, close the bleeder, then pump the pedal half way to the floor repeatedly until the piston works its way out of the caliper and pedal pressure builds up. If the piston is already out, just "irritate" the brake pedal by hand a couple of times, then open the bleeder screw once more to burp out the last few little bubbles that got pushed into the caliper.
Was this
answer
helpful?
Yes
No
Friday, April 14th, 2017 AT 9:39 PM

Please login or register to post a reply.

Recommended Guides