Thread: Brake rotor bed in procedure

If its new rotors and pads then I test them and then just drive it normally.

If its old rotors and new pads then I test them and just be careful if the brakes might get hot for a few hundred km as the pads bed in a bit.

Originally Posted by PeterH

Hi all, I'm about to install new brake rotors on my 2001 4.6, just wondering if anyone has a preferred brake rotor bed in proceedure?
I'd be interested to know how you go about it on your P38.

I read the following on the DBA website:

1. After installing new disc rotors &/or brake pads, perform 8 to 10 slow-downs applying moderate pressure from approximately 50 – 60 Kph without coming to a stop.

2. Make an additional 2 to 3 slow-downs applying heavy pressure from approximately 60 – 70 Kph without coming to a stop.

3. DO NOT DRAG BRAKES!

4. Allow at least 15 minutes for brake system to cool down.

Thanks, Pete.

When working as a Spanner Spinner the company I worked for insisted this was how new brakes were to be bedded in - we always did a full road test very similar to what you have listed - I was told it was to bring the temp up slowly in the new disks to prevent premature warping - no idea if it was actually true but since then I have always bedded in new rotors and pads slowly.

I believe the not coming to a complete stop is to prevent the hot pads causing hotspots on the rotors. In the hilly place I live I try to judge my braking for that reason, especially in the Ford. BAs eat rotors enough already.

I always take it easy with new discs as well, getting them up to temp slowly. However, the main killer for warping them is to finally get them hot and then have to wait for traffic or so. Auto's require you to keep your foot on the brake and what happens is that the rotors start cooling except where the pads touch, causing them to unevenly cool and thus warp...

Keep that in mind when you bed them in In fact, even after that when and if you need to brake long/hard and you have the opportunity, leave ample room so that you can slowly wiggle the car forward over the course of a minute so that you can evenly cool the rotors.

-P

Another important thing when fitting new rotors, is to clean them.
They usually have some anti rust coating on them. Use brake cleaner or acetone with clean white cloth or paper.
you will see when it's clean.