While trying to change my pads i noticed my rotors seem loose, also i cant get the brakes to stop grinding, squealing after reassembly.

Hello Stephen,

Disk brake pads do have little metal tangs attached to the backing plates that will "squeal" when the pads wear down to a point of requiring replacement. Which you noticed and repaired.

Still have that pesky noise? Even after pad replacement?
This is caused by vibration between the pad and the caliper piston(s)or the guide pins.

You may have noticed a thin metal backing plate on the back of the pad...purchase some Brake Anti Squeal Compound and apply it to the backing plates (both pads) to stop this annoying racket.




Ate Plastilube Brake Anti Squeal Compound 35ml Tube

A grinding or rumbling noise can also be symptoms of a wheel bearing or constant velocity joint in a driveshaft. A worn wheel bearing can also cause a 'whistling' sound (as can a worn CV joint).

A grinding noise with brakes is either worn pads causing metal to metal contact on the brake disk/rotor, or the brake backing plate catching on a spinning rotor ... or a loose/missing anti squeal brake shim (they stop the pads from rattling and vibrating).

However, as you say a mechanic has looked at the brakes and can't find anything wrong .. I think I would begin to suspect a wheel bearing or constant velocity joint on the driveshaft (front wheel drive cars).

Yeah, bad brake pads and now because you let it get to the point of grinding, you'll probably need a new rotor or drum too. When the brakes start to wear down and they need changing there are wear indicators built into the pads that start to make a high pitched squealing sound. If you ignore it for to long then it starts to grind because all the brake material is gone and you are now hitting metal on metal when you try to stop.

He changed the brakepads with worn rotors. You need to get your rotors turned. The old brakepads had worn down in a specific shape with how the rotors have worn down. If the rotors were worn down enough because of failure to change the pads in time, then new pads will skip along the surface of the rotor from which they clamp down on, causing the shaking you feel when braking. Go get it done at a shop, it shouldn't be much...somewhere in the range of $20 per rotor depending on the shop you go to.

Check caliper for correct operation. The sliders, did you grease them?

One of the brake pads on one of the front brakes is probably wore out and rubbing metal to metal. Your rotor may be damaged to some extent. If it just started it may not be bad but you need to replace the brake pads.

there are special anti-vibration shims that go between the pad and its mounting surface ... also some systems use a special lub or adhesive .. some high end pads have built in anti squeaking stuff (thats very effective)....some of those also improve brakeing and reduce dusting and wear .. nice pads and i use them a lot but they do cost more ..here is one such site...

http://www.federalmogul.com/en/AftermarketSolutions/NorthAmerica/BrakingSolutions/Products/BrakePads-Shoes/WagnerPassengerVehicle/Thermoquiet/

...you shouldnt have to put up with squeaking brakes .. the shims usually work fine . retrofitting them is about the same amount of work as installing new pads however they dont cost much.. they should have been installed at your last pad change but they are left out frequently and are often not included in low cost pads ... .

some cars specify that you have to adjust the mounting gap for the pads . they provide shims to do that on better brake brands but not on low cost products .. again the result is noise ...

watch out for low cost pads that have a poor distribution of metalic fill ... those really mess up the rotors ..(look for heavely grooved rotors) ...there were lots of them sold in this country a year or two ago ..
..

You, Probably will, Brake Squeal is NOT a new problem.
Disc brake's have been Squealing since, They, became
factory installed on chevrolet in 1971. Before, that they,
were a option. In 72 they even had a bulleton how, to
FIX it. And, no it didn't work.
With That said, Any time you replace Brake pads you,
should always re-surface the Rotors.
Why? First you may start to notice a pulsation as the
pads ware (sometimes! ) The best way to avoid, brake
squeal is to manchine the Rotors put, the blue membrain
sealent on the back side of the pads. And hope that works!!
Some brakes Pads squeal JUST SQUEAL??
You, Could do the same Brake job the same as you did
this one and, they may NOT Squeal.WHY, I WISH I NEW. They
sell all types of STUFF to stop Brake noice DON'T waste your $$.

Squealing usually indicates that the brakes are in need of replacement. There is a small piece of metal that as the brake pads wear comes in contact with the metal rotor. When the pads get close to being worn away the tab touches the rotor and it squeals. The tab can also click.
When the pads are worn away completely the metal backing comes in contact with the rotor and it grinds. Grinding is bad. It means the car's brakes are metal to metal. This will cause damage to the rotors resulting in an even more costly brake job.
You should have it taken care of ASAP.
I hope this helps.

Break squeal can be stopped by applying shims or anti-squeal compound to the pads.