Brake Bedding a cure for Brake Judder?

[QWIKWHIP]

I still say it's a materials problem. Like Squids post said about the pads and rotors needing to be compatable. I just don't think the Titan pads and rotors are a match made in heaven. However, mine are fine, go figure!

[HavockWK]

Originally Posted by Quad T

Actually, normal driving is not going to get the job done. The pad and the rotor are never going to be given the opportunity to go through such important molecular changes. This bedding in process is something I know a thing or two about because it can be the difference between life and death on the race track.

Ironically enough in my circle of friends we sort of joke about bedding pads all the time because we call it "smoking them", as in "hey, want to get together and smoke some pads?"

Normal driving is not going to produce these kinds of effects, and with race pads that operate at temps exceeding 1,200 degrees they often display billows of smoke when being bedded because their operating temps are so much higher than street pads. And if that is not cool enough, some pads throw sparks the first one or two times they are used because the pad material has such a high concentration of metals.

Bottom line – I not only bed my track pads, I always bed my street pads.

Since the racing pads are so much more extreme than the average street pad, I can see a need to smoke 'em. (racing is all about smokin something right? ) But for the street pads, it still seems that smoking them is overkill.

Also, when you bed them, the first time, exactly how much of the pad gets the proper treatment? The molecules .25" deep aren't going to be the same as the ones on the surface that are smokin. Do you repeat this process every couple months to keep them properly bedded down? I'm asking honestly here, so don't be offended.

[rkawski]

Originally Posted by HavockWK

but I don't over heat the brakes like this says. This process seems a little extreme to me since I know people who do their own pad replacements (non-Titans) and don't follow this procedure and don't have any subsequent issues.

Squid is correct. However most folks don't do it. The only reason those of us in know do it is we have experience with racing brake pads. Once you start getting into AutoX or HPDE's are road courses you start finding out these things.

But again most don't and also most folks don't have a clue how well a vehicle should stop or when to replace brakes.

[Squid]

Originally Posted by HavockWK

Since the racing pads are so much more extreme than the average street pad, I can see a need to smoke 'em. (racing is all about smokin something right? ) But for the street pads, it still seems that smoking them is overkill.

Also, when you bed them, the first time, exactly how much of the pad gets the proper treatment? The molecules .25" deep aren't going to be the same as the ones on the surface that are smokin. Do you repeat this process every couple months to keep them properly bedded down? I'm asking honestly here, so don't be offended.

Just the first time. As for the brakes smoking, all it's saying is don't freak if they do.
The highlighted part is what I think is maybe happening to a lot of city commuters. (And could explain why some get the Judders with less than 2000 miles) They get the truck don't bed the brakes. While stuck in traffic they over heat the pads, imprint pad material on the rotors and it just gets worse from there.(bedding hardens the rotors the same way they harden a steel sword)

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.

My theory suggest that even if the Mech does bed the brakes when the T.S.B is done. They don't cool the brakes long enough to prevent this imprint, thus repeated trips to the service department.

One last thing.Lets remember the weight we're trying to stop.If you don't bed the brakes in your compact car, I doubt that normal people will have a problem.
But this truck accelerates faster, and weighs more.

[Austin]

I've got just under 17K miles on my Titan. I had the brake TSB performed at around 9K miles, and a second time around 13K miles. My truck is once again in need of attention to the brakes - it shudders with enough force to slosh soda out of a 3/4 full 12 oz can.

I bedded the pads and seasoned the rotors when I got the truck (new off the transport) and after the TSB was performed both times. Not good enough... the damn thing still judders. The Titan's brakes are either too small or the caliper sticks.

I usually follow Baer's bed-in and rotor seasoning procedures - Street pad bedding or Race pad bedding. Street rotor seasoning or Race rotor seasoning.

I'm a racer, both autox and track, and I've gone through more pads and rotors in the last 6 years than I can remember. I once went through (down to the backing plate) a set of Porterfield R4 pads trying to keep up with a race prep'd Porsche on a track event - I could keep up with him out of the corners & gain on him in the corners, but I couldn't come close to braking as late as he was...

[Squid]

If the calipers are sticking then it won't really matter what you do. The TSB will clean the rotors up but not for long. And it won't matter what size rotor they put on if the caliper isn't releasing then the judder will always return.
Still leaves a lot of questions as to why some and not others? I'm over 16,500 miles now.

Did you back off your lugs to 85 ftlbs and if so was it before or after the first TSB? I backed mine off the first day I got it.( I believe it was a Jettech sugestion.) It was a pretty active topic back in August.

[Quad T]

Originally Posted by rkawski

Once you start getting into AutoX or HPDE's are road courses you start finding out these things.

Very true.

Originally Posted by rkawski

But again most don't and also most folks don't have a clue how well a vehicle should stop or when to replace brakes.

In addition to how you should actually use them. I remember back when I was a newbie and my instructor was teaching me threshold breaking, I feel fortunate to have learned on a non ABS car.

[raceboy]

Originally Posted by Squid

I now have over 16,000 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.
Is it possible that some are doing this and some are not?
For stop and go driving this very important and I have a hunch that this might be part of the problem.

It would be really nice if someone who goes in for a Brake TSB would Bed their brakes in and then periodically update us as to the condition of their brakes.

It would be even better if it was someone who has had the TSB already done at least once.

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.


By the way you can do a search on the internet or call a local brake shop to verify that this Info is legit.

I use my Titan to tow my Formula Ford 2000 so I am very familiar with bedding in pads and rotors. After the second repair I performed a bed in procedure which I normally wouldn't do on a street car because I have never had to. I did it again the last time and still 2500 miles later I had the same problem.

The rotors for this trucks weight are simply too small. It's not they overheat. They come up to temperature too quickly but that probably isn't the problem. The problem is probably that they cool too quickly in the surface area not covered by the brake caliper itself. Because it cools unevenly and quickly, that is more than likely what causes it to warp.

[Squid]

Originally Posted by raceboy

I use my Titan to tow my Formula Ford 2000 so I am very familiar with bedding in pads and rotors. After the second repair I performed a bed in procedure which I normally wouldn't do on a street car because I have never had to. I did it again the last time and still 2500 miles later I had the same problem.

The rotors for this trucks weight are simply too small. It's not they overheat. They come up to temperature too quickly but that probably isn't the problem. The problem is probably that they cool too quickly in the surface area not covered by the brake caliper itself. Because it cools unevenly and quickly, that is more than likely what causes it to warp.

Did they replace the rotors or just turn them? I'm now at over 18,000 miles and still no judder. I also tow a 16 ft trailer with a Kobota tractor and all it's attachments.

[raceboy]

Originally Posted by Squid

Did they replace the rotors or just turn them? I'm now at over 18,000 miles and still no judder. I also tow a 16 ft trailer with a Kobota tractor and all it's attachments.

Turned twice, replaced twice. New pads all 4 times. Do you have any fairly steep grades where you tow?? I do.

Even turning the rotor give you a virgin friction surface so if it was just a friction layer problem, bedding the brakes should solve the problem. Unfortunately turning the rotor also removes precious material to absorb heat so each time I just had the rotor turned the problem occured faster.