Grinding noise when braking gently

[Roker]

Can I compare with someone else. 

When I am going slow and gently press the brake I hear a grinding noise like the disks are rusty .

The car ha only got 34,000 km up, I cannot think that this is the pads already

[yossarian247]

You need to change your title as its the same as your other thread which is actually about headlights!

It may be that the disks are slightly rusty, as hybrids use regenerative braking wherever possible they are more gentle on the conventional brakes so corrosion can build up on the disks. 

 

 

[Roker]

On 11/29/2023 at 10:01 AM, yossarian247 said:

You need to change your title as its the same as your other thread which is actually about headlights!

It may be that the disks are slightly rusty, as hybrids use regenerative braking wherever possible they are more gentle on the conventional brakes so corrosion can build up on the disks. 

 

 

All I'm asking, does anyone else have this, is it normal

[Derek.w]

all cars & all types do a gentle braking noise when its just starting to bight or when its changing across from one brake system to another on say a steep hill.

[Cyker]

I don't really notice unless the windows are down and I'm leaving for work in the morning, then it can be quite pronounced, esp. after rain or if I haven't driven for a few days+.

My discs tend to have a patina of rust in the mornings, moreso than my previous cars, probably because I use the friction brakes far less thanks to my tendency to coast and the regen doing the majority of the braking most of the time.

The short version is it's probably normal.

 

[TonyHSD]

Normal if it goes away after few stops and some drive. The yellowish patinas Cyker is talking about here 

Not normal if the discs are pitted and corroded and not able to clean after some driving, usually in town drives the brakes get cleaned better as more often they are used so you really need around 40-50 miles and the discs should become nice and clean, if they don’t means your system needs cleaning and slider pins lubricated again. 
Here a brake discs that shows signs of bad brakes that require cleaning procedure. 

And here how should look discs on car that has perfectly working callipers and sliders. Smooth and shiny surfaces. 

[Cyker]

It's quite a contrast to my previous cars, which had mirror-smooth brake discs because I used them so much  

It is a nice change not having to change my brakes every couple of years!!

 

[bigblock]

I had this grinding noise on my Auris 1.8 TS 2016. The dealer said find a quiet bit of road and do some hard braking now and again. It did stop the grinding but really defeats the objective. Drivers who look where they are going don't need to brake hard 🤫. So how should you drive these days?

[Rhymes with Paris]

25 minutes ago, bigblock said:

I had this grinding noise on my Auris 1.8 TS 2016. The dealer said find a quiet bit of road and do some hard braking now and again. It did stop the grinding but really defeats the objective. Drivers who look where they are going don't need to brake hard 🤫. So how should you drive these days?

Get on a straight bit of road, dual carriageway if one handy,a good look behind and if clear, brake heavily from around 60 mph to around 20 mph a couple of times.

Obviously not if icy or snow, but ok normal winter conditions.

My mileage is low nowadays, and mostly town,so I like to do this once a week or so to keep the discs clean also checks the brakes are working properly.

As you probably know,discs get surface rust overnight when it's wet, and this rubs that off before it can start pitting the discs, causing expensive replacement MOT failure etc.

But of course,if you just wish to brake gently with good anticipation all the time, that's fine too , but will not clear the discs, and you will get the grinding noise again.

[Mojo1010]

Think OP is talking about the hybrid braking action at the very end of a stop. If the assumption is correct then it's normal, nothing to worry about. Regen braking comes first.

[AndrueC]

I've always had this on my cars because I've always been a 'driving without brakes' guy. That plus parking in a garage guarantees a fine 'patina' on my brake discs 🙂

Not mentioned in that article is that it's also a safer way to drive. You have more thinking/acting time in an emergency and you also have all of your braking effort to add in if needed. If you're already braking when you spot the emergency you may have little or no additional braking available to you.

I was reminded of this a couple of days ago while stopped at some road works. A car came up behind me at speed then braked at the last minute and ended up stationary behind me for a minute. A waste of fuel, unnecessary wear on their discs/pads and given that it was a very cold morning both of us could have ended up swapping our details. And for what? Absolutely no gain on their part.

[TonyHSD]

Agreed with all above. 
The hybrids biggest issue on the brakes are the sliders. These has grease inside protected by a rubber boot. But because the brakes almost never gets warmed up, or been hot there is moisture that enters inside the slider pins , cause corrosion and make them stuck. Because the callipers are floating type to work the outer pad the calliper needs to move inward when brakes are applied, however if the pins are corroded and solid the only pad that works is the inner one, the results are less biting feel and not possible to clean the rust from the discs. Hard braking might not help either. 
For the regenerative braking as long as you step harder on the pedal the actual brakes will engage and clean the discs. No need to be abusive just few moderate and more progressive late brakes when coming off the motorway are simply enough. 

[Cyker]

6 hours ago, bigblock said:

I had this grinding noise on my Auris 1.8 TS 2016. The dealer said find a quiet bit of road and do some hard braking now and again. It did stop the grinding but really defeats the objective. Drivers who look where they are going don't need to brake hard 🤫. So how should you drive these days?

If the grinding bugs you a lot then that's the easiest way to deal with it; Alternatively just ignore it, as it's not a problem that will e.g affect the performance of the brakes in any meaningful way.

Thankfully my Mk4's so noisy I don't really notice it over the road noise anyway (And the rock and metal helps too    )

[dervdave]

Spaying your brakes with Bilt Hamber Atom Mac works great

[bigblock]

22 hours ago, Cyker said:

If the grinding bugs you a lot then that's the easiest way to deal with it; Alternatively just ignore it, as it's not a problem that will e.g affect the performance of the brakes in any meaningful way.

Thankfully my Mk4's so noisy I don't really notice it over the road noise anyway (And the rock and metal helps too    )

A fellow metalhead. Cool.🤩