Toyota Tundra Forum

I don't know about anyone else but I have always bedded my brakes in on new vehicles and on my last truck I figure that's one of the reasons I never did have the brake problems that most owners suffered from. (Ignore the mileage part because I now have over 92,000 miles on my second set of rotors and pads.)



Brake Bedding

Brake pad glazing is caused when the brake pad friction material is overheated.
This results in crystallized friction material on the pad surface and the brake disc.
Typical symptoms of glazed brake pads include: Poor stopping performance, vibration or brake judder, and cracks or fissures in the brake pad material.
Pad glazing is typically caused by operating the brake pads at a temperature above the specified temperature range of the friction material or not properly following the 'Bedding-in' instructions for the brake pads. Always follow the manufacturers brake pad bedding-in instructions and use a brake pad that has a temperature range that is sufficient for its intended use.
And this is bedding in :

For optimal use of any given brake system, the pads and rotor have to be compatible with each other. The bed-in procedure establishes that compatibility between the pad and rotor. This is achieved by a combination of rubbing speed, temperature, line pressure, and Inertia. Bed-in is also influenced by pad and rotor material chemistries. It is always recommended that only compatible pads and rotors be used in any given application.
Bedding in advantages:
1. Gradually heat treats the rotor and eliminates any thermal shock in the rotor.
2. Burn off volatiles and moisture from the resin that is near pad surface.
This will eliminate ?green fade.?
3. Establish a layer of transfer film about a few microns thick on the rotor surface. Shearing of the film during friction is an effective source of friction force. Otherwise, when using a freshly ground rotor without the transfer film, the main friction force would come from cutting, plowing, or scoring the asperities on the rotor surface. This leads to inconsistent braking effectiveness.
4. Mate the two surfaces to a near perfect geometrical match, so that the contact area is high, and therefore the friction force is increased.
5. The performance of a fresh rotor/fresh pad system would be inconsistent. This is due to ever-changing structures and properties of the two mating materials. Bed-in of pads and rotor will form a stable transfer film.
6. If bedding in procedure is not applied, a stable transfer film may not be established for a long time. In other words, the rotor surface would have to be constantly regenerating a film that is not quite stable for a long time. This effect would reduce the performance and increase the wear.

I now have over 38,000 miles on my truck and no judder. I wonder if it's because I always perform this procedure on all my new vehicles (even motorcycles) and whenever I do a brake job.
For stop and go driving this is very important and I have a hunch that this might be part of the problem.

Bed In Procedure:

From a speed of about 60mph, gently apply the brakes to slow the car down to about 45mph, then accelerate back up to 60mph and repeat. Do this about four or five times to bring the brakes up to operating temperature. This prevents you from thermally shocking the rotors and pads in the next steps.
Make a series of eight near-stops from 60 to about 10 mph. Do it HARD by pressing on the brakes firmly, just shy of locking the wheels or engaging ABS. At the end of each slowdown, immediately accelerate back to 60mph. DO NOT COME TO A COMPLETE STOP! (Note: With less aggressive street pads and/or stock brake calipers, you may need to do this fewer times. If your pedal gets soft or you feel the brakes going away, then you've done enough. Proceed to the next step.)
During this process, you must not come to a complete stop because you will transfer (imprint) pad material onto the hot rotors, which can lead to vibration, uneven braking, and could even ruin the rotors.
Depending on the pads you are using, the brakes may begin to fade slightly after the 7th or 8th near-stop. This fade will stabilize, but not completely go away until the brakes have fully cooled. A bad smell from the brakes, and even some smoke, is normal.
After the 8th near-stop, accelerate back up to speed and drive around for as long as possible without using the brakes. The brakes will need at least 10 minutes to cool down. Obviously, it's OK to use the brakes to avoid an accident, but try to minimize their use until they have cooled.
After the break-in cycle, there should be a blue tint and a light gray film on the rotor face. The blue tint tells you the rotor has reached break-in temperature and the gray film is pad material starting to transfer onto the rotor face. This is what you are looking for. The best braking occurs when there is an even layer of of pad material deposited across the face of the rotors. This minimizes squealing, increases braking torque, and maximizes pad and rotor life.
After the first break in cycle shown above, the brakes may still not be fully broken in. A second bed-in cycle, AFTER the brakes have cooled down fully from the first cycle, may be necessary before the brakes really start to perform well. If you've just installed a big brake kit, the pedal travel may not feel as firm as you expected. After the second cycle, the pedal will become noticeably firmer.

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Good Gawd that is one ugly Tundra.

wow, I've never heard of that.

Thanks, I will bed-in my brakes on my T-150 when it gets here.

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2007 Tundra DC SR5 5.7L 4X4
TRD, Leather, Backup Cam, Tow
Blue Streak

Mods: Black Line-x bed, Husky Liner floor mats, Yota billet shifter, Flowmaster Super 40 muffler (dual in/dual out) with rear exit SS exhaust tips, Firestone Destination 285 65 18 MTs. Truxx 3-inch lift/level kit. Bushwacker pocket fender flares. 4-cleat Tundra deck rail kit. Westin bull bar.

or is it a T-250? hmmmmmmmmmmm.

I read about brake bedding when Squid posted the procedure on another forum. When Nissan provided a new rotor design for the Titan, (because of brake judder caused by rotor warping), I decided to give it a shot.

Much of my commute is braking for curves, (some marked as low as 10 mph). I think compared to someone that drives on freeways ... that actually move at 65 mph, I probably brake at least 10x as much. Of course many deal with stop 'n go freeways and the hard braking associated with that, so their brakes get a good workout too. Anyway, 25K-30K miles and no problems with the brakes, so maybe equivalent to 250,000 miles of brake use for some!

Can't say for sure that it was the bedding that provided this level of service, but doesn't seem to have hurt.

I'll always bed the new brake rotors and pads ASAP. Thanks Squid!

I always wondered why the folks in the city were having brake problems. I live in the mountains drive on 1-2 lane roads most of time. While I use the gears as much as possible, I use the brakes a lot, but rarely ever panic stop.
Since I got back from LA, I now know why the city folks have problems.Even though it is fairly flat, all I could smell on the LA freeways was burning brakes. These people are going from 80-0mph dozens of times a day and not getting to their destination any faster than I was just poking along at 50-60mph.

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2007 Tundra DC Limited 5.7L 4X4
TRD,NAV,TOW
Xlerator Exhaust
aFe Stage 2 CAI
BFG AT/KO 285/65/18
Desert Sand Mica

I did this according to the instructions that Squid posted here and it worked exactly as described to every detail (spongyness, long pedal, a little smelly, etc.).

Now the day afterward, and brakes are completely normal and I feel they are happy and healthy.

What a wonderful site this is! Thanks.

Okay, way back in the late 60's I was a mechanic and a state licensed brake installer, but I had not been trained or instructed in bedding the brakes. Of course back then most of the vehicles we worked on used drum brakes. We used a machine to arc the shoes. (breathed in a lot of asbestos doing that - not a known hazard at the time or at least not mentioned)

Anyway, after reading the procedure and doing a bit of research I decided to give it a try. I felt like I was abusing my truck in the process of "bedding the brakes". That is not the way I normally treat my vehicles. I experienced all that was described in the procedure. Afterwards I had a look at the rotors and could see what was described in the write-up. So I presume the procedure was a success.

It will be a while before I have any idea about the benefits of it all. At least this old dog is still willing to learn new tricks.

Thanks for the education!

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2007 Tundra RC LB SR5 5.7L 4x4, Tekonsha Prodigy Brake Controller, JCW Side Bars, AMP BedStep, 12K+miles and no problems besides the tailgate beginning to fail.

I've been "bedding in" brakes for years after learning the benifits from racing stock cars. I have actually EXPLODED a brake rotor on my race car by not doing any "bedding" or hard stopping before the racing events started for the night. What I found out from the rotor manufacturer was that by not "bedding in" or "heat cycling" my brakes before severe use, the rotor exploded because the moisture in the rotor (from the manufacturing process) expanded at such a great rate that it destroyed the rotor. This is something I remember whenever I put new rotors on ANYTHING! A few easy stops with cooling intervals, then I can "bed" them in. Just something I learned the hard way.

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2007 Tundra DC 5.7 V8
SR5 Long bed 4x4
Tow, Ext mirrors, Backup cam
Blue Streak , St Stl Running boards
A.R.E. Fiberglass Cap

Squid's suggested method seems a more precise way of doing the vague "break-in" instructions you get from the manual for new brakes, with similar desired results. I've apparently lucked out, mixing highway and city driving. My brakes ended up dead smooth, braking action better than pedal pressure might predict, no squeaks, and little dust on the wheels. Mainly what I was told was no hard stops at first, letting the pads seat a bit, then gradually increasing to harder stops to get the temperatures up over a period of a few hundred miles. Seat first, then when contact area is established, go for the heat. I still might cryo treat the rotors and drums.

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04 AC TRD 4.7L 4WD. I bought a Tundra before Tundras were cool.

Great post. Excellent info. Thanks