gsimon767

Installed four rebuilt stainless sleeved O ring calipers and new pads. Now brakes sometimes squeal when driving and stops squealing when brakes are applied. What needs to be done to stop squealing?

Mountainoakie

To stop the squealing you must bleed the air that is still trapped in the calipers and/or brake lines.

gsimon767

I know these brakes can be difficult to bleed so I used a Motive Products pressure bleed system at 10 lbs pressure. I bled once tapping calipers to dislodge air, let the system sit overnight bled again the next day tapping calipers again. Brakes work great stopping with no pull. Pedal is firm- engaging with no slop in the initial pedal travel.

Not disputing your advice just don't know what more I can do to get air out.

MelWff

I think air has nothing to do with it. Apply some anti-squeal compound on the back of the pads.

http://www.walmart.com/ip/42006176?r...569769&veh=sem

jb78L-82

Or your brake pad type....

BEVO76

You need to bed the new pads to the old rotors....did you do that after the swap? If you swapped rotors and didnt shim then you have runout.

BEVO76

It could be this too....cheap pads are squeak prone.

TCracingCA

Can squeak and squeal too! Did you change brands or types of pads???

I usually will feather the leading edge of the new pads slightly, so they are not riding on the edge, to give them the ability to maybe seat across the face faster!

Duane4238

The Wagner pads I used the last time I changed pads came with a stick on insulator that went on the back of the pad. You can also get a permatex blue spray that goes on the back of the pad and does the same thing. The squeal you are experiencing doesn't come from the pad material contacting the rotor. It comes from a vibration between the pad backing plate and the metal pistons in the caliper. The two vibrate against each other and cause a high frequency squeal. If you were as old as me, you wouldn't hear the squeal.
Duane

drwet

If you choose to try putting something on the back of the pads, make sure it is a lubricant and not an adhesive. Anti squeal compound is usually an adhesive. As the pads move slightly when applied, and adhesive will cause the pistons to rock in their bores, eventually taking out the seals. A little grease on the back of the pads can help reduce the vibration between the piston and the pad that can cause squealing. I have used Never-Seize with mixed results. fact is, some pads nowadays simply squeal. Its a function of the material they are using. traditionally brake pads were made with asbestos. That stuff was always quiet. Now they use ceramics, and metals, and all kinds of stuff. Some of it squeals. You may need to try a different set of pads.

gsimon767

Pads are new. Came with the calipers from Lonestar. Seems like they had a Teflon type pad of some kind on the piston side.

Reused old rotors after roughing surface with DA sander. Checked runout with dial indicator. Was in spec.

Made several stops from 50-60 MPH to bed pads to rotors.

TCracingCA

Therefore I think I had better get more technical here!

Ok the thread is about squeal, and that is pad to rotor!

And squeak is pistons to pads!

BEVO76

Lol

Rescue Rogers

Use the anti squeal lube on back of pad. Cheapest easiest solutions first

TCracingCA

Use the anti-squeak lube and not the anti-squeal lube for that application!

Sorry LOL

Tampa Jerry

If you have bedded in the brakes and applied the anti-squeak pads on the back of the discs, try putting a small bevel around the outside edge of each disc. I use a file. I would not add grease to any part of the caliper or piston back. It will melt and cause problems. Likewise I would not use a sander or sandpaper on disc pads. You can embed sand from the paper into the disc and ruin your rotor. It is OK to sand down or break the glaze on a rotor as long as you thoroughly clean the rotor with brake cleaner. Good luck. Jerry

TCracingCA

So stock not my cup of tea!

But I don't see a problem using these lubes on the backs because that is what is done on these new cars without problems! Naturally you want to use it in the proper amount and keep if to the backs of the pads! I use a bench grinder and a stone wheel to hit my pad edges for a split second of beveling!

blue by you

I always spray the back of the pads with brake quiet, no squeals

Rescue Rogers

http://www.eeuroparts.com/Parts/6563...ke-Spray-ASBS/

http://www.ebay.com/itm/Permatex-241...679451&vxp=mtr

http://www.amazon.com/s?ie=UTF8&page...0anti%20squeal

Anti Squeal

TCracingCA

Probably some college grad who drives a Prius!