new rotors break in

golfclub

Well-known member
Joined
Feb 11, 2014
Location
Victoria B.C.
TDI
2000 TDI Golf
Have put new rotors on the car to get rid of the pulsing brake peddle.
I have gone through this before and it always comes back after a few thousand km.
The ones I just took of I did the break in thing.
I have read that rotors don't warp, that it is caused by pad material transfer.
Anyhow, do you guys do the brake rotor break in procedure or do you just install
them and drive?

Thanks
 

Nuje

Top Post Dawg
Joined
Feb 11, 2005
Location
Island near Vancouver
TDI
2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
I read about the whole pad/rotor break-in thing (instructions came on a set of PowerStop pads/rotors), so followed those instructions (a few medium hard braking; then three REALLY hard brakings (100+kph down to 30kph) about as quickly as you can). No wobble in the brakes.

After that, though, I read a bit more here and the general consensus seemed to be that if you're one who needs "performance braking" (e.g., out on the track or something like that), it's a "best practice", but for the average you and me, not necessary.

So, on my recent rear brake job on my mk7, I just drove the car normally after the new pads/rotors and guess what - they're fine. Feel way better than the pulsing I had on the old set (120K km).

The conclusion I've come to is to avoid heat-soaking the pads - like, coming down off a mountain and then parking the car 5min later and setting the parking brake while the brakes are still too-hot-to-touch.

Is this in any way backed up by anything other than a low-single-digit sample size which is barely more than anecdotal? Nope.

So, I hope I've answered your question. ;)
 

03TDICommuter

Veteran Member
Joined
Dec 8, 2016
Location
So. Cal
TDI
01' NB, 5spd
Have put new rotors on the car to get rid of the pulsing brake peddle.
I have gone through this before and it always comes back after a few thousand km.
The ones I just took of I did the break in thing.
I have read that rotors don't warp, that it is caused by pad material transfer.
Anyhow, do you guys do the brake rotor break in procedure or do you just install
them and drive?

Thanks
Did you measure the rotor lateral runout after installing the new rotors? If you didn't, and your lateral runout is excessive, your problems are going to come back.
 

Zak99b5

Veteran Member
Joined
Apr 30, 2021
Location
Albany NY
TDI
2003 Jetta TDI
When I install new pads & rotors, I like to go out and do a number of hard braking events to heat them up. Thing is, you can’t come to a stop and keep the brakes applied while you can still smell them or you’ll get too much pad material transfer in that spot and a thickness variation. So I keep driving till things cool down afterward.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
When I install new pads & rotors, I like to go out and do a number of hard braking events to heat them up. Thing is, you can’t come to a stop and keep the brakes applied while you can still smell them or you’ll get too much pad material transfer in that spot and a thickness variation. So I keep driving till things cool down afterward.

This is what I do to my brakes when first installed. The only thing I might add is I try never to buy chinese rotors and pads. Idparts has Fremax and Zimmerman rotors (European) and I have come to really like Akebono pads (USA).
 

DuraBioPwr

Veteran Member
Joined
Jan 28, 2020
Location
Eastern Washington
TDI
2004 BEW Jetta (5spd)
Yup like said above. Never stop hard and just sit there in one spot with brakes still applied. If need to stop hard leave your self some room to creep and move the rotor under the pad. Yes its the material transfer on one spot when crazy hot that 'warps' them.
 

golfclub

Well-known member
Joined
Feb 11, 2014
Location
Victoria B.C.
TDI
2000 TDI Golf
On the set I just took off I did put a dia indicator on them when I did the install.
I think it was less than .002. When I removed them one side showed .006 and other other one was .002
I will do a reading on the ones I just installed and report back. I have only used Zimmerman or Fremax rotors.
I am aware of the things that can cause problems and avoid doing them. I also am not using the brakes in
a harsh manner ie. racing etc.
Think I will just use them and not bother with the bedding process this time.
 

gforce1108

Top Post Dawg
Joined
Aug 2, 2006
Location
Newburgh, NY
TDI
04 Jetta GLS BEW, 14 Audi A7 V6 TDI, 13 Porsche Cayenne V6 TDI
Most pulsing is caused by worn lower control arm bushings. Install the TT version instead of stock. I've never had mkiv rotors warp - even cheap ones (Detroit axle ran $112 for a set of 4 rotors, pads, clips, brake cleaner and fluid - 3 sets installed on different MKIV cars).
 

golfclub

Well-known member
Joined
Feb 11, 2014
Location
Victoria B.C.
TDI
2000 TDI Golf
Well that's interesting.
I have new LCA bushings waiting to go in. They are the TT type.
The car is now getting a little harsher over bumps as I replace bushings with the TT type.
Have the solid rear bushings in the car already.
 

gforce1108

Top Post Dawg
Joined
Aug 2, 2006
Location
Newburgh, NY
TDI
04 Jetta GLS BEW, 14 Audi A7 V6 TDI, 13 Porsche Cayenne V6 TDI
Well that's interesting.
I have new LCA bushings waiting to go in. They are the TT type.
The car is now getting a little harsher over bumps as I replace bushings with the TT type.
Have the solid rear bushings in the car already.
The control arms move backwards under braking, hit their limit and bounce back forwards causing the pulsing feeling. Very common on these cars. The TT ones are cheap enough that I keep at least one pair on the shelf ready for any mkiv that pops through. I haven't swapped rears with the Cupra style - yet but I've done at least 10 cars with TT LCA bushings - no noticeable additional harshness.
 
Top