348 Brake Squeal Issue... Tearing my Hair Out!!!

For about 2 months now I've been fighting brake squeal on the fronts. To explain... Pads were getting a bit worn and decided to change them out on all 4 corners. Replace rear rotors as well, and used Ferodo FDB451 on all corners. Front rotors looked good and measured within tolerance. Bed them in! Brakes work fine, lots of bite, and once 'warmed' up, front brakes squeal unless I'm hard on them!!!! Certainly not the way to drive in traffic, and embarrassing to boot!
What I have done since:
1) Relubed all pads/pistons & castings in case of corrosion/rust, etc..... no change
2) Replaced front rotors with another used set that was machined, still in spec, bed again.... same headache!
3) Verified pistons are all moving well... not stuck, chamfered pads on leading edges. squeal still!
4) Purchased new pads, different cheap metallic brand, lubed and bed again... headache still there!
5) Purchased new rotors, still squealing .... Arrgh!
6) Replaced pads with the original new Ferodos, re-bed, and squeals still
Honestly, I have done multiple searches on squealing brakes. The original pads that I removed were the standard Ferrari pads with the 2/3 shim behind pad... never squealed. The Ferodos come with soft/spongy backing shim. The semi metallics came with a full metal shim. I have read many positive things on the Porterfield pads, but feel, if the Ferodos are bad, then they should be squealing on all 4 corners!!! I've tried different lube companies... Arrrgh!
What am I missing???

 

The squeal is caused by the back of the bad on the piston. Imagine using your wet finger to make a wine glass “sing” as you spin around the edge. The back of the pads “vibrate” at high frequency making the piston “sing” as it vibrates when not under load. A hard brake push will quiet them temporarily and then it comes back.

Rotors and pads have to be done together. As in you can’t reuse after they have been “matched together” a previous install. They get a specific ware patter and once the rotors was turned or pad replaced without rotor change or any combination there of, they squeal.

My key is new pads with new rotors, cleaned and lubricated with a. Very sticky backing product on the back of pad and shims that prevents the “singing” on the piston. That is the culprit. Mismatched wear patterns and nothing keeping the pad from sliding back and forth on piston at high frequency.


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I assure you, I have the same problem. can be a groove on the skate..

 

Not a big deal. Mine did that.

As Rob pointed out, the squeal is from the back of the pads.

Put some high heat, anti squeal lube on the back of the brake pads.

Brembo includes a small packet of the stuff with all their brakes.
Other options exist and can be had at most auto parts places.

The grease wears out and needs to be renewed once in a awhile.

 

Thanks for your replies. I assure you there is plenty of new 'grease/brake goop' between pistons and pads, as well as any surrounding pad sliding areas! 2 different brake goop companies, recommended by auto part stores, as well as my initial goop which I have used for many years with MB's and other vehicles! Seeing as though the new rotors have less than 300 kms on them, I have to assume another set of new pads will work in mating?? bed in etc. Maybe a light scuffing up of the new rotors to accept the new pads? The stupid thing is they don't squeal when starting out, but 10 mins in.... embarrassing!!!
'Ga68' what do you mean "can be a groove on the skate.."??? Are you referring to the caliper framework the supports the pads? If so, been checked over & over, LOL!
Another thing, on becoming an expert, R & R-ing the calipers to change out rotors, those pesky spacer shims....! I'm assuming they are there to fine tune the caliper spacing, equidistant to the rotor? Mine have 2 shims each, and was pleased to find a solution to mounting the calipers without loosing the shims. Simple crazy glue holds them to the calipers long enough to end the fight of dropping out before the mounts bolts are threaded. Is there any other reason for these shims?

 

Take it to the track, that should seat them in.

If that dont work you have uneven braking pressure or a misalignment somewhere

 

Well, purchased some Porterfields (AP345) tonight. Going to verify everything, again, LOL! Pads will be here in a couple of days. Hoping a different, better, compound will react positively!

 

Dang, you have tried all the tricks I have ever heard of for squealing brakes!

 

Maybe you need a few "track laps" to really get them bedded?

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Have you tried anti squeal shims? One last idea, I recall a 300 ZX that had an "unsolvable" squeal problem. Turned out to be a cracked rotor.

 

To the original poster I feel your pain! I have the same problem on my right rear and like you have tried every possible remedy. I even replaced the flexible section of the brake line and bled the brakes all four corners the game could be a possible restriction or possibly air in the system unfortunately it made no difference. I will definitely be watching this post. The good news on mine it only does it when reversing on the right rear and only when cold once it warms up it's fine... but it is loud all the neighbors look out their windows

 

These are the Ferodo FDB451 pads I was using. The blue backing is a spongy 1/8" backing that is supposed to absorb any vibration/squealing... works fine on the rears???
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I've tried 3 different sets of rotors(last ones are NEW), as well as another cheap set of semi metallics. In "another life", I raced semi-factory Yamahas' in the 70>80s!!! I'm almost as hard on the streets, but have grown up a bit, and choose my places. That said, I am sure I have bed in the pads!
John, have not tried these 'anti- squeal shims' unless they are the same as the foam backed Ferodos, My cheapy pads came with some metal shims, but were even worse... and no, they were full shims, not like the Ferrari 3/4 shim.
Polo...heheh... my original Ferrari pads squealed the rears/same way in reverse/cold, was actually another reason to change up... LOL
My plan, when the Porterfields arrive, is to scuff up the new rotors, clean everything again fervently, add brake paste/lube and follow the sellers directions... as their shop ( LPI Racing) recommends a gradual bed-in, rather than stomp the sh-t out of it.
Always ready to learn... still have some hair... LOL!

 

Your Ferodos pictured do not appear to be beveled try taking a hand grinder and putting a nice bevel on the leading and trailing edge and see what happens? Incidentally my buddy has been at Mercedes for 35 years said when they get a car in that squeaks and they have tried everything they wind up replacing the caliper! They say that over time the Piston wears a certain way and does not push perfectly on the pad as it would have when it's new and it usually solves the problem but that's only when one wheel is squeaking.

 

Interesting since you can just replace the pistons.

 

Sorry, from my 1st post... "3) Verified pistons are all moving well... not stuck, chamfered pads on leading edges. squeal still!" Good thought on the pistons, although the squealing is on both fronts..... You would think that the new pads would wear in to any minor piston offset wear when bedding in.... but plausible. The original pad set when removed looked square, but that was just looking at them! Hopefully the change in pad compound will alleviate this headache. I will follow up, Porterfields arrive next Monday/Tues.

 

Agree with you although mechanics these days are part replacers!!! Labour is time, time is money, not their dime... we all know the rest!

 

I am in no way an engineer, but often wonder why there was not an “insert” in the pistons to absorb the vibrations??? I have Carbon Brakes on my ZR1. Like all carbon brakes, they can be pretty quiet if heat cycled and “burnished in” but noise will come back, rinse, wash and repeat! Only good thing is they will basically never wear out in mild street use.

I hate the Brembo brake compound on factory pads for Ferrari. Way to soft and dusty. I ran Porsche 964 Turbo pads on my cars. Used a very inexpensive Carbon Cermic pad I bought on my WORLDPAC account. About $65 front and rear. Buy these pads all the time for all my euro cars and love them. Low dust, low noise. Great stopping for street use. Not for track though. Best deal I found. You cannot turn these rotors and I never did anything but swap pads on my cars. Left the lip as I have a set of original brakes I was saving for a rainy day. No more 355’s, so I guess I will sell someday ;-)


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Rob, thanks for suggesting another alternative pad.
Someone else I was chatting with suggested reversing the pads... by that I mean taking my rear Ferodo pads and shoving them in the front calipers, and vice versa. It will probably prove something, but right now I'd hate to incur any more headaches, so I 'll just wait and replace. Many on here have recommended the Porterfields in the brake squealing threads.

....Maybe I'll get bored tomorrow and switch out the left side.... getting pretty quick at this... LOL! Geez, I'm starting to overthink this....

 

So I've been thinking about your brake squealing issue and may have a possible solution. First of all let me say that when it comes to brakes, opinions vary and they vary wildly. But I personally believe you should always go with a non-metallic, or semi, organic soft pad which of course makes a big huge mess with black dust but you're softer pads are always going to be quieter. Having said that check out the photo of my Mercedes S550 pads which by the way are the quietest brakes that I've ever had on a car....Ever. Notice they are directional with arrows stamped in the pad and notice closely that the anti squeal rubberized backing material has semicircular pieces strategically cut out so that the Piston pushes on certain areas of the pad to avoid squealing. The material is about the thickness of a typical business card. These are Factory Spec. And I know if you put them in backwards they will squeal like the Dickens because I accidentally did that once. Anyway, perhaps you could take an exacto knife and cutout and replicate these semicircular cutouts for your Ferrari and it may help...worth a try?
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PS. And one final thought make sure that your anti rattle Clips are in good shape although that's really hard to determine might be worth just replacing them on principle.

 

The Brembo pads that I have are directional and have the backing pad placed off-centre. They also have two grooves in the friction block.

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Ah yes....correct....I too have Brembo on all 4 corners. I only have the squeal on my right rear only in reverse and only when cold which I can live with.

 

Reverse and cold is “normal”.... rolling opposite direction cold on one wheel is hard to correct. Is what it is.


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The ferodos the op pictured have no cut outs on the backing plate....solid. Brembo did it for a reason.

 

The parts diagram also shows directional pads with two grooves, same as the Brembos I have. The "Brembo" pads have word "GALFER" stamped on the steel plate and I just found that the same GALFER pads also come with "Ate" logo. It appears that the manufacturer puts "Brembo" or "Ate" just to match the brand of the calipers, otherwise the pads are the same.

https://www.ebay.com/itm/Ferrari-355-Rear-ATE-Brake-Pads-New-70000875-/151559961938
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