Rear brakes.

[madasahatter]

I recently had a squeal from off side rear brakes. Also it was getting to hot to touch, so i replaced both callipers discs pads all hard wear. Now the near side rear is the culprit, it does not start from the get go.

Any ideas would be appreciated.

[LIJO151]

Possibly caliper slider pin.

[madasahatter]

Every fitting is brand new.

[true blue]

Strange one when new parts have been used .Are the callipers new or refurbished ? could be a faulty calliper . Ideas.  I would remove pads ,check for excess paint or burrs on back plates where they fit into the calliper , re bleed calliper ,push piston fully back with clamp or retraction tool a couple of times to ensure it is free ( use a block of wood to prevent piston popping out ) check the handbrake action is O K and smooth and the shoes are not dragging .If this is all O K I would look to replacing the flexible hose ,as the bore may be restricted

Dave

[madasahatter]

Callipers new Toyota not refurbished, pads discs and slider pins new. Pad spring returners new brakes been bled, only thing not renewed is hand brake pads,

but they are like new i never use the foot brake.

[true blue]

O K only thing I would now suggest is foot brake seized or sticking ,In my experience if the brake is never used it can stick ,Try backing off the adjustment and operating it 30-40 times see if it is any better

Dave

[Mr Vlad]

Yes. As above. There's been a post or 3 over the years about this. It's best practice to Use the park brake because it can seize due to lack of use.

[Beamish]

 

Were the "Anti Squeal shims" replaced/refitted?

Perhaps a little coppergrease or brake paste on the contact points of the pads would help alleviate the problem.

 

[madasahatter]

Copper grease was put on all contact points, i have had the calliper and disc off again today. Nothing is binding that i can see, hand brake works fine

and realises fine. Brake pad shims have copper grease on the back. Like i say everything is brand new, it is a baffling thing. Either disc is warped or new calliper

must be the fault i am believing??

[GS300h2014]

My suggestion would be to get the two rear tyres off the ground using axles stands or a centrally placed jack & try turning the wheels by hand to find out what is binding. Try doing this after pressing the brake pedal down.  If the brake master cylinder or a brake load proportioning valve is binding then the continuing high pressure will not allow the pads to retract causing the symptoms you describe.

[madasahatter]

I have already done this where i work. Like i say it is a baffling thing, i drove the car this morning for about 4 miles no sound.

But the sound could take half an hour before it shows. Then next day its fine again for a limited time.

[true blue]

If you are happy with everything you have assembled then it could be a faulty calliper, which is why I asked if callipers were reconditioned .I have seen this with reconditioned calliper but not a new one

Dave

[madasahatter]

No all done correctly i came on here for input, which people like yourself give. It is much appreciated from one and all.

I have never come across it before on any car. I work in a bus garage so plenty of mechanic input and thoughts.

True Blue mentioned hand brake, so first thing i tried this morning. But it is working fine no clucking when released, holds perfectly.

[Mr Vlad]

How are the wheel bearings? Just a thought as worn and dry ones create a lot of heat which I'm sure you know.

[madasahatter]

No noise what so ever from the bearings, i thought that myself. I keep putting the windows down listening, i hate uninvited noises .

Good call thou Vlad.

[MrTrendizzle]

On 2/14/2023 at 5:24 PM, madasahatter said:

Every fitting is brand new.

When fitting the new pins did you get a thin straw brush (Made of metal) and floss the holes? I had the exact same issue. Brand new pins and calipers and they still got stuck. Invested in a tiny straw cleaner https://www.tube-brush.co.uk/products/prod_2704096-Steel-Cylinder-Wire-Brush-4mm-with-Loop.html something like this. I got mine from a local cheap shop for £2.  

The amount of gunk and rust that it removed was insane and fixed my issue. I also coated the slider in a thin coating of grease and not packed it in as that made a suction type seal (When you remove the pin it slurped and popped)  

Failing that before i replaced the slider pins i removed the rubber seals from the pins until i could replace them which also helped as a temp measure.

[steve2006]

Very good point made in the above post, the slide pin holes on the calliper carriers being blind do get clogged with old grease.

I used the same type brush and isopropyl alcohol to clean out the years of stale grease and crud in there.

Given the rubber inserts on the pins I also found that a thin smear of RRG ( Red Rubber Grease) provided long lasting lubrication.

[Mr Vlad]

What's the latest with your rear brakes Keith? Only ask as I had a look at mine today and give the sliders a clean and fresh lube.

[madasahatter]

Still the same i contacted seller of callipers and he said its unusual for original ones to be faulty. I bought a new head light that was worse than the

one i was replacing from a dealer. Just because its new does not mean its perfect, day off today so all coming off again. 

I am doing the lot front and rears, fronts are not that old about 5 months. Strange thing i went a full day with not a sound its driving me nuts.

[madasahatter]

Update as of Wednesday , took brakes apart all around no visible signs. Re greased every thing did a 20 mile drive in stop start simulation,

and not a sound from anywhere so could be happy days again. Thank you once again for every ones comments, a big happy family helping out.