6SpeedOnline - Porsche Forum and Luxury Car Resource

6SpeedOnline - Porsche Forum and Luxury Car Resource (https://www.6speedonline.com/forums/)
-   Aston Martin (https://www.6speedonline.com/forums/aston-martin-39/)
-   -   Budget brakes, turning rotors (https://www.6speedonline.com/forums/aston-martin/395136-budget-brakes-turning-rotors.html)

SinisterSF 08-13-2016 09:56 PM

Budget brakes, turning rotors
 
I do all my own maintenance on my DB9 and I'm wondering if anyone has ever had their rotors turned rather than just replacing them every time?

I have stock rotors, no interest in the brembo rotors, too expensive and a waste since I'm not racing or doing any hard braking.

I'm not sure what material the stock rotors are made of, but I'd like to get them turned once. I'll replace them next brake job.

telum01 08-13-2016 10:33 PM

I'd suggest you measure their thickness and compare to minimum thresholds. Typically, with your usage it shouldn't be a problem having them turned.

SinisterSF 08-14-2016 04:24 AM


Originally Posted by telum01 (Post 4549371)
I'd suggest you measure their thickness and compare to minimum thresholds. Typically, with your usage it shouldn't be a problem having them turned.


Any idea what the minimum threshold is? I've got a service manual but I haven't dug through it to see if that's in there.

SinisterSF 08-14-2016 06:16 AM

Dug through the manual:
Brake discs Front
Initial thickness 32 mm
Min. thickness 30 mm

Brake discs Rear
Brake disc initial thickness 28.0 mm
Brake disc Min. thickness 26.0 mm

Brake pads
New pad thickness 9.4 mm
Minimum lining thickness 2.5 mm

Brake pads Parking
Minimum lining thickness 6 mm

Timodc 08-14-2016 02:00 PM

Typically when slotted rotors are machined, a small ridge can develop on the opposite side of the slot, which can cause some slight noise and strange pad wear. There are some places that use a certain technique to avoid this, but I'm not sure how it's done. If I were to do it myself, I would just machine the inner and outer lip of the rotor, and bed the new pads to the existing rotor surface.

blue2000s 08-14-2016 02:55 PM

Why are you looking to get them turned? Are the brakes pulsing?

SinisterSF 08-14-2016 03:23 PM


Originally Posted by blue2000s (Post 4549563)
Why are you looking to get them turned? Are the brakes pulsing?

No pulsing or anything, I do feel as though I have to push down pretty hard to get good braking though, not that I've owned other AM's to compare to. The brakes on my wife's BMW are so touchy in comparison. She hates when I drive her car, always brake checking the **** out of her because I'm used to brakes that require some force. The brakes are a bit squeaky when first pulling her out of the garage, probably because she only gets driven once every week or two.

So I figured if I'm changing pads I would turn rotors this round then next brake change slap on some new rotors.

SinisterSF 08-14-2016 03:24 PM

I do want to do a full brake fluid bleed on it also, maybe that will firm up the pedal some. Any pointers for a fluid change?

telum01 08-14-2016 03:53 PM

I'm finishing up a DIY video and write-up right now. Got the bulk of the write-up on my website earlier today, video should be up tomorrow. Pretty straight-forward and easy to do, same as most modern brakes. Info in here, too:
https://www.6speedonline.com/forums/...tch-fluid.html

deckman 08-14-2016 04:50 PM

If they aren't vibrating or pulsating I would leave them alone and just do the pads. If it hasn't been done in a long time flush the fluid.

blue2000s 08-14-2016 05:35 PM


Originally Posted by SinisterSF (Post 4549577)
No pulsing or anything, I do feel as though I have to push down pretty hard to get good braking though, not that I've owned other AM's to compare to. The brakes on my wife's BMW are so touchy in comparison. She hates when I drive her car, always brake checking the **** out of her because I'm used to brakes that require some force. The brakes are a bit squeaky when first pulling her out of the garage, probably because she only gets driven once every week or two.

So I figured if I'm changing pads I would turn rotors this round then next brake change slap on some new rotors.

If there's no pulsing and the rotors are not thinner than the min spec, don't do anything with them.

The Aston brakes are not as grabby as any of my other cars. I also find them harder to modulate than typical. This is mainly a pad characteristic. You could make the brakes more grabby when cold and at initial application with a change of pad material.

007 Vantage 08-14-2016 11:47 PM

Brake modulation is most likely a brake fluid issue. Most of the Astons out there have bad brake fluid in them. If you are not changing the fluid religiously at least once every 2 years (if not sooner) then your brake fluid is probably black sludge right now. It's by far the #1 most overlooked maintenance job.

Motul 600 or Castrol SRF will provide 10% better feel and last 2x as long as normal brake fluid. It can also handle way more heat during aggressive driving

blue2000s 08-15-2016 01:12 PM


Originally Posted by 007 Vantage (Post 4549733)
Brake modulation is most likely a brake fluid issue. Most of the Astons out there have bad brake fluid in them. If you are not changing the fluid religiously at least once every 2 years (if not sooner) then your brake fluid is probably black sludge right now. It's by far the #1 most overlooked maintenance job.

Motul 600 or Castrol SRF will provide 10% better feel and last 2x as long as normal brake fluid. It can also handle way more heat during aggressive driving

Even with a brake fluid bleed 8 months ago, the modulation is still not what it is on my Lotus or even Subaru.

telum01 08-15-2016 01:19 PM

So long as your brake fluid is fine, modulation is heavily based on pad material.

BMW-North 08-15-2016 02:36 PM


Originally Posted by Timodc (Post 4549532)
Typically when slotted rotors are machined, a small ridge can develop on the opposite side of the slot, which can cause some slight noise and strange pad wear. There are some places that use a certain technique to avoid this, but I'm not sure how it's done. If I were to do it myself, I would just machine the inner and outer lip of the rotor, and bed the new pads to the existing rotor surface.

This ^ is good advice (trimming back the outer/inner lips that may have formed) along with a brake fluid flush after you verify that the rotors meet the minimum spec and the runout is within tolerance. Have the rotors cleaned then bed the new pads using a driving/braking protocol (Search Google). As far as the squealing goes I solved that with CRC Disc Quiet for $4 (I know it's not recommended for shimmed pads - I'm not tracking so it's fine for my once a week use) The PO paid AM dealer huge to fix the squeal issue and it never worked. (New shims and re-bedding the pads)


All times are GMT -6. The time now is 08:55 AM.


© 2024 MH Sub I, LLC dba Internet Brands