GR86 Grooves in brake discs

Jokurt

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Hello,

I've noticed there are grooves in the brake discs. The grooves in the front discs are only in a few positions, but relatively deep/distinct. In the back they are more evenly spread out.

Hard to explain so here are some pictures:
1788686405748.webp
1788686548929.webp

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For about half a year the car only gets driven on weekdays. It's parked outside and after a rain the brake pads usually stick to discs. Sometimes I could hear something scraping for the first few meters.
Is this normal wear for these circumstances? At which point do the brake pads and or discs need replacements?

Thank you.
For now, I drive around with the groovy discs🤓
1788687700805.webp
 
Oooh, that doesn’t look great. I reckon you may have caught some debris (maybe iron from the discs) in there, or the pads are damaged.
The discs should have fine concentric lines all around with no grooves that can be snagged with a finger nail.
The image below is a shot of my OEM discs. Excuse the rust spots as they’ve been on a shelf in my garage. The second image is of my BBK as fitted.
I think you might want to look at getting those changed down the line …
OEM set:
IMG_1122.webp


BBK (fitted):
IMG_1124.webp
 
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I had grooves in my discs which were caught during my service in July, the right rear brake pad (which was admittedly low and needing replaced within the next few months anyway) had also stuck which had to be jemmied off. Occurred some time between the car's MOT in January and the service in July, circa 27,000mi. Cost me a grand at the dealership for parts and labour so save yourself some money and at least order the pads and discs yourself!
 
Thank you two for the replies
Oh man, compared to your discs, Sonic, mine look completely knackered. o_O
@Renzokuken86 was it one grand for rear or for both axles?
My next service is in November, I better sort it out before.
I have emailed my dealership for a quote.
Depending on the amount I will ask a Subaru dealer what they charging. Are the brakes of the 2.Gen BRZ the same as the GR86?
Or maybe I look for a BBK, but there are only a few street legal options in Germany and they are expensive.
 
Thank you two for the replies
Oh man, compared to your discs, Sonic, mine look completely knackered. o_O
@Renzokuken86 was it one grand for rear or for both axles?
My next service is in November, I better sort it out before.
I have emailed my dealership for a quote.
Depending on the amount I will ask a Subaru dealer what they charging. Are the brakes of the 2.Gen BRZ the same as the GR86?
Or maybe I look for a BBK, but there are only a few street legal options in Germany and they are expensive.
Yep it was for all four pads and rotors. Half the cost was the labour haha
 
Wouldn’t go anywhere near a dealer to do pads and discs, any decent independent garage locally to you will be much better value.
 
Wouldn’t go anywhere near a dealer to do pads and discs, any decent independent garage locally to you will be much better value.
Absolutely and if you want to shop around locally, Euro car parts do a set of front Brembo discs for £55. Many other available online at that or cheaper prices too.
 
I try to avoid going the toyota dealers in my region as best as possible. Only for the annual service stamp because I don't know any good indi garage.
I'd like to have the toyota quote as a reference and for the man maths to justify a BBK 😅 not that I need the performance, its the aesthetics.

At the Subaru garage near me works a mechanic who drives a modded gen2. BRZ. My hope is that they are more competent.

Now I have to gather some informations and prices.
 
Wouldn’t go anywhere near a dealer to do pads and discs, any decent independent garage locally to you will be much better value.
Yeah unfortunately the issue crept up during my service, the plan had been to grab something off Fensport within the next few months. I'll make sure I get as much from my money as I can out of these new OEM ones!
 
Yeah unfortunately the issue crept up during my service, the plan had been to grab something off Fensport within the next few months. I'll make sure I get as much from my money as I can out of these new OEM ones!
Do like I do, get yourself a set of rubber chocks and always park up in-gear, handbrake off, and put the chocks in place. Saves me having to 'crack' the brakes when I reverse down the driveway. The OEM discs/pads were absolutely terrible for sticking ...
 
Do like I do, get yourself a set of rubber chocks and always park up in-gear, handbrake off, and put the chocks in place. Saves me having to 'crack' the brakes when I reverse down the driveway. The OEM discs/pads were absolutely terrible for sticking ...
I've always parked up my GR86 in this fashion. The handbrake doesn't use the rear pads and discs. There's another small set of shoes inside the centre drum of each rear wheel which are activated when the handbrake is pulled. Mine used to crack on my old GT86 when parked for a few days until I relied just on the gearbox.
 
so here is an intermediate update

Replacing the brakes with parts in OEM size, sourced from the internet it would be around 150 € for the front axle and 130 € rear axle. With a rough estimation of labour costs between 200 € and 400 € it sums up to 480 € - 680 €.

If found an old invoice from 2018 when the brakes of my Lexus IS250 got replaced. Toyota charged 807 € total ( incl. 250 € labour cost). I assume it didn't get cheaper in the last years.

Speaking of Toyota dealerships. On Monday afternoon, I emailed my local service dealer to request a quote. On Wednesday, I called because I hadn't heard back from them. Maybe the email didn't go through. The response was: "didn't you already asked for a quote by Mail? I thought someone was working on that. Did you look in the SPAM Folder?. I will take care of it." And all of that in that arrogant and annoyed tone of voice. To this day I did not receive a quote. Maybe I made the mistake to say it was not that urgent, but over a week for a simple quote...

Option 2 is a BBK Kit. In Germany the selection is very limited as far as I could find out.
There is the Brembo Kits, but they are stupidly expensive. Just the front Axle is 4000 € and more. Then there is a six piston Kit from Torax for 1800 € and it comes with papers for relatively easy TÜV approval. The catch is, the replacement parts limited in choice, hard to come by and very expensive.

The last BBK on my list is the one from UMCparts, which was discussed in the brake upgrade thread. It comes with Brake calipers powder coated in a RAL colour of choice, DBA Brake discs and pads for the front and rear axle, all fitting materials and braided brake lines for 1900 €. The price seems reasonable, the included DBA discs and pads alone cost 1000 € on the internet. And I don't have to source all parts by myself.
As discussed in the brake upgrade thread the caliper comes with 44/40 mm pistons and this results in a higher front brake bias. The car is my daily with the occasional spirited driving, no plans to go on a racetrack. Would I notice the shift in brake bias?
The included Brake discs are the DBA 4000 Series T3 and the pads are from the Xtreme Performance Series. Would it reduce the bias shift if brake discs and pads from the Street Performance Series were used?

Nevertheless, I got in contact with them, and they send me the documents, they use for the TÜV approval.

Finally, I rang the Subaru dealer, and asked if they even work on a GR86 and if they could fit the BBK and workout the details with the TüV. The woman on the phone was super friendly was like: "Yes, that is no problem, the BRZ and GR86 are basically the same car with different stickers. Send the BBK documents, and we discuss it with the TüV Inspecter."
 
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