Front brake "run-in"


#1

Hey folks! Happy Saturday. I’ve been changing brakes for years . . just changed the front disc brakes on my old 89 honda accord. I’ve never “run them in” like some people talk about, anybody have any comments on this procedure? I’ve never done it, & usually get 30-35k out of a set of front brakes, about 70-75k on rear drums, never had a problem. Comments?


#2

The brake pads will take a few miles to wear to conform to the brake rotor. Until then, braking effectiveness may be a little down. If the brake rotor wasn’t severly grooved, it should “run in” (wear to conform) soon. It’s not something I lose a lot of sleep over.


#3

I’ve never done a conscious brake run-in. Just driving where you want to go handles the run-in all by itself.


#4

[b]Anyone who has serviced brake systems over the years, knows that there is a proper run/break-in procedure to follow when brake friction surfaces are new.

This insures that the friction surfaces get imbedded or happy with each other. Failing to run/break-in on a new brake job can result in glazed friction surfaces. Glazed friction surfaces can result in unwanted brake noise, or uneven brake friction surface wear.

To do a proper brake run/break-in proceedure when new pads and new/resurfaced rotors are installed, get the vehicle up to 35-40 MPH. Then when it’s safe, apply the brakes firmly to slow the vehicle down as quickly as possible without locking the brakes or engaging the ABS. Repeat this about a half a dozen times allowing a minute or two between braking events to allow the brakes to cool down.

Do this, and you’ll find you’ll never have brake noise and the brakes will last longer. But that’s assuming the rest of the brake job was done properly.

Tester[/b]


#5

Thank you Tester . . . I’ll give it a try. Rocketman


#6

Why try to fix what doesn’t appear to be broken? Mileage is relative to the vehicle, driving conditions, driving style and so many other factors that it is hard to generalize on what is “normal”. Even so, that’s a decent lifespan from my experience and I wouldn’t change a thing.


#7

Yeah, I know Anon . . but the procedure is so simple and makes sense . . and I believe that Tester has more experience than I do. Can’t hurt, might help . . . and I’m always willing to try something new to see how if affects my vehicle. Thanks to both of you for your input. Rocketman


#8

I always seat mine in like Tester said. It helps living near a back road with almost no traffic.

I started doing my own brakes (then everything else) after I had my rotors and pads replaced at Tuffy. They must not have seated the pads and glazed, because the next time I needed to stop quick, the car barely slowed with both feet on the pedal and from 30mph I hit the car that was at least 3 seconds ahead. Never again have I gone to a chain shop for any work besides tires.


#9

They probably never wiped down the rotors.

I’m due to have my fronts done too. My spine is in such bad shape now (degenerative disc disease) that I can no longer do my own work. It’s breakin’ my heart to have to pay domeone to do this, and no shop will just replace the pads without turning or replacing the rotors. I understand why, but I’m still bummed out.

For those who’ve been doing their own for years, be aware that if you replace your car with one with ABS there’ll be a slight change to the protocol. Simply backpressuring the system to push the caliper pistons in can damage the ABS. Fluid need to be run out the bleeder valves when pushing the piston in.

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