IPD sale XeMODeX - Experts in Volvo Electronics
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy anything with this and it helps MVS!

new brake rotor

Help, Advice, Owners' Discussion and DIY Tutorials on Volvo's stylish, distinctive "P2" platform cars.

2001 - 2007 V70
2004 - 2007 V70 R
2001 - 2007 XC-70
2001 - 2009 S60
2003 - 2007 S60 R

BladeRider
Posts: 10
Joined: Sat Apr 07, 2018 6:21 am
Year and Model: 2001 V70 2.4T
Location: Antwerpen
Has thanked: 3 times
Been thanked: 0
Belgium
BladeRider

new brake rotor

Post by BladeRider » Wed Apr 29, 2020 6:11 am

Hello!

I've purchased two new rear brake rotors. They are original Volvo. One of them has a milling on the side, which I thought and the store confirmed, that it is from balancing. What seems weird to me is that the milling is as wide as the rotor.
Did anyone see something similar? Thank you!
disc.jpg
disc.jpg (27.82 KiB) Viewed 120 times

jimmy57
Posts: 6613
Joined: Fri Nov 12, 2010 9:25 am
Year and Model: 2004 V70R GT, et al
Location: Ponder Texas
Has thanked: 4 times
Been thanked: 258 times
jimmy57

Re: new brake rotor

Post by jimmy57 » Wed Apr 29, 2020 7:54 am

The pad contact on older platforms not across the face to the edge. There is 2-3 mm of non contact area. On models where this is true the metal can be removed on full edge as with yours. On the models where the contact is within a narrow margin of edge due to not having the extra weight the margin introduces, the balance cuts are deeper down into the vent region and leave 3mm or more behind the surfaces.
These users thanked the author jimmy57 for the post:
BladeRider

BladeRider
Posts: 10
Joined: Sat Apr 07, 2018 6:21 am
Year and Model: 2001 V70 2.4T
Location: Antwerpen
Has thanked: 3 times
Been thanked: 0
Belgium
BladeRider

Re: new brake rotor

Post by BladeRider » Wed Apr 29, 2020 8:23 am

jimmy57 wrote:
Wed Apr 29, 2020 7:54 am
... the balance cuts are deeper down into the vent region and leave 3mm or more behind the surfaces.
Thanks. There is no vent region on these rear rotors on my car. Only in the front rotors. I've seen the balancing milling on the front ones and it is indeed as you said. I was just uneasy about the rear one extending to the whole width (only one has a milled portion, not both).
I'm not a pro mechanic, just a DIY one and I lack the experience of seeing many parts and the way they're made.

User avatar
- Pete -
Posts: 719
Joined: Fri Dec 06, 2013 10:13 pm
Year and Model: 01, 04, 04, 04 V70's
Location: Minnesota/Wisconsin
Has thanked: 60 times
Been thanked: 108 times
United States of America
- Pete -

Re: new brake rotor

Post by - Pete - » Wed Apr 29, 2020 10:41 am

It’s a little hard to tell from the picture, but it almost looks like it cracked off.
Can you put up a slightly clearer image?
2001 V70XC 146k
2004 V70 AWD 141k
2004 V70R M66 144k
2004 XC70 287k
2006 XC70 155k Sold

User avatar
oragex
Posts: 4960
Joined: Fri May 24, 2013 6:20 am
Year and Model: S60 2003
Location: Canada
Has thanked: 99 times
Been thanked: 290 times
Contact:
Canada
oragex

Re: new brake rotor

Post by oragex » Wed Apr 29, 2020 12:23 pm

I've yet to see such 'balancing' on any car at the junkyard. The question is, why would this particular rotor need balanced ? These are all cast then machined with the same parameters, why would one become unbalanced ?

BladeRider
Posts: 10
Joined: Sat Apr 07, 2018 6:21 am
Year and Model: 2001 V70 2.4T
Location: Antwerpen
Has thanked: 3 times
Been thanked: 0
Belgium
BladeRider

Re: new brake rotor

Post by BladeRider » Wed Apr 29, 2020 12:47 pm

- Pete - wrote:
Wed Apr 29, 2020 10:41 am
It’s a little hard to tell from the picture, but it almost looks like it cracked off.
Can you put up a slightly clearer image?
Clearly machined, not cracked. And very little. Brand new, got it sealed with Volvo stamping on it and labels on the box.
WP_20200429_20_40_10_Pro.jpg
WP_20200429_20_39_58_Pro.jpg

BladeRider
Posts: 10
Joined: Sat Apr 07, 2018 6:21 am
Year and Model: 2001 V70 2.4T
Location: Antwerpen
Has thanked: 3 times
Been thanked: 0
Belgium
BladeRider

Re: new brake rotor

Post by BladeRider » Wed Apr 29, 2020 12:50 pm

oragex wrote:
Wed Apr 29, 2020 12:23 pm
I've yet to see such 'balancing' on any car at the junkyard. The question is, why would this particular rotor need balanced ? These are all cast then machined with the same parameters, why would one become unbalanced ?
Many rotors come with a milled out notch like this:
https://www.powerstop.com/mill-balanced ... tor-notch/

I've also got a set of Brembo rotors for the front and they are both milled like in the link above. It's just that I haven't seen it yet on a rear rotor and all the way to the lateral surface.

User avatar
oragex
Posts: 4960
Joined: Fri May 24, 2013 6:20 am
Year and Model: S60 2003
Location: Canada
Has thanked: 99 times
Been thanked: 290 times
Contact:
Canada
oragex

Re: new brake rotor

Post by oragex » Wed Apr 29, 2020 3:28 pm

I see. Given that most rotors don't need this, I wonder if there have been some issues during the casting process. Not necessarily something to worry, but I'd say it's perhaps one of the few that weren't made 'perfect'. Maybe the melted iron didn't properly fill all areas of the mold. I would rather call this a 'reject' especially give the OEM standards.
These users thanked the author oragex for the post:
BladeRider

Post Reply
  • Similar Topics
    Replies
    Views
    Last post