pads, rotors and calipers changed...still vibrating when braking

So after reading up on the uneven thickness rotor causes and solutions to prevent it, the main preventatives they describe is the proper selection of pads specified for application, and the proper bedding procedure performed when new braking surfaces are installed. The bedding procedure for street pads they describe is quite detailed, requires traffic free long stretches of roadways, and if is interrupted should be started all over again.
I've done this before with street performance pads that came with instructions for bedding them in, but I never even thought that regular pads should be done as well.

Do any shops ever perform a bedding process on brakes they install?

Do any high end manufacturers with expensive braking components ever perform the steps?

Does anyone ever do this, or is the process just ignored and performance is accepted without the procedure?

For reference bedding info
I just follow PowerStop's general 40 to 10 aggressive (X5) and 35 to 5 moderate (X5) then drive to cool them down.

Actually it just occurred to me I'm kinda lucky to live on a relatively quiet, straight, flat stretch of 60mph paved county road....
 
I agree. It could be the rear. Rear has rotors not drums.

The rotors were replaced when I bought the vehicle in the rear as well.

I did do some work in the rear. Replaces the brake pads. Lubricated the sliders, caliper pins, and fixed and adjusted the e-brake.

But it's possible the rear rotors might be warped.

It just feels like it's coming from the front but I could be fooling myself.
D60 has the ansswer
 
So after reading up on the uneven thickness rotor causes and solutions to prevent it, the main preventatives they describe is the proper selection of pads specified for application, and the proper bedding procedure performed when new braking surfaces are installed. The bedding procedure for street pads they describe is quite detailed, requires traffic free long stretches of roadways, and if is interrupted should be started all over again.
I've done this before with street performance pads that came with instructions for bedding them in, but I never even thought that regular pads should be done as well.

Do any shops ever perform a bedding process on brakes they install?

Do any high end manufacturers with expensive braking components ever perform the steps?

Does anyone ever do this, or is the process just ignored and performance is accepted without the procedure?

For reference bedding info

Akebono ProAct pads don't require bedding.

When a car is new no one from Ford or Chevy etc took it off the assembly line out to the street to bed the pads before putting the vehicle on a truck to ship to the dealer.
 
I just follow PowerStop's general 40 to 10 aggressive (X5) and 35 to 5 moderate (X5) then drive to cool them down.

Actually it just occurred to me I'm kinda lucky to live on a relatively quiet, straight, flat stretch of 60mph paved county road....
It's not all that easy to find a stretch of road where you can slow down down from 40 to 10 five times then 35 to 5 five more times without people behind you getting road rage.
 
Akebono ProAct pads don't require bedding.

When a car is new no one from Ford or Chevy etc took it off the assembly line out to the street to bed the pads before putting the vehicle on a truck to ship to the dealer.
I hear that, but I'm just playing devils advocate here..
 
I have had a tough time with vibration when braking at high speeds on concrete (interstate highways) in my Tundra for years. I always thought it was the front rotors.

About two months ago, I started hearing a noise coming from the rear when braking with no load or with a light trailer (1200 lbs). I ordered all new OEM rotors and pads and replaced them, flushed the fluid (as I always do), etc. I had done a pad slap on the rears about 75-80k miles, now has 158k miles.

The rear pads were about 50% worn (Powerstop Z36 pads) and there was a smidge of grease on the slide pins. But evidently there was build up on the rotors or they had runout. I didn't measure.

Anyway, now, all good. No vibration, no noise. Bottom line - it's not always the front brake system.
 
Do any shops ever perform a bedding process on brakes they install?

Do any high end manufacturers with expensive braking components ever perform the steps?

Does anyone ever do this, or is the process just ignored and performance is accepted without the procedure?

For reference bedding info

1. GOOD shops will perform a bed-in procedure, whether it's what the tech "always does" or they might actually read the brake pad manufacturer's instructions. BTW, most all instructions overlap and include ~ 10 hard stops from 45-60 mph to 10-5 mph, repeat and then drive for ~10 minutes without touching the brake pedal as much as you can. I'm fortunate to live in an area where I can perform a bed-in procedure that fits any instructions.

2. Yes, or they instruct the dealer to do so or instruct the dealer to advise the 1st owner to go do it when they leave the lot. I bought a vehicle from a guy that was taking delivery of a 2022 Tundra. When we parted ways, he said he was going to perform the bed-in procedure on the brakes. Note that he and the salesman had already done 12-15 miles of "test driving"... This was a new, fresh off the truck Tundra, nobody had ever driven it.

3. I do the bed-in procedure on all front brake jobs I do. I'd say that the process is ignored more than 50% of the time by most. This, along with many other reasons, is why I do all my own work.
 
When a car is new no one from Ford or Chevy etc took it off the assembly line out to the street to bed the pads before putting the vehicle on a truck to ship to the dealer.
Bedding brakes isn't mandatory, but it's probably a good practice where feasible. With new vehicles coming off the assembly line, no, it's not feasible so it doesn't happen.
 
1. GOOD shops will perform a bed-in procedure, whether it's what the tech "always does" or they might actually read the brake pad manufacturer's instructions. BTW, most all instructions overlap and include ~ 10 hard stops from 45-60 mph to 10-5 mph, repeat and then drive for ~10 minutes without touching the brake pedal as much as you can. I'm fortunate to live in an area where I can perform a bed-in procedure that fits any instructions.

2. Yes, or they instruct the dealer to do so or instruct the dealer to advise the 1st owner to go do it when they leave the lot. I bought a vehicle from a guy that was taking delivery of a 2022 Tundra. When we parted ways, he said he was going to perform the bed-in procedure on the brakes. Note that he and the salesman had already done 12-15 miles of "test driving"... This was a new, fresh off the truck Tundra, nobody had ever driven it.

3. I do the bed-in procedure on all front brake jobs I do. I'd say that the process is ignored more than 50% of the time by most. This, along with many other reasons, is why I do all my own work.
If street pad needs bed in, it is some North Korean junk.
Track pads or street high performance pads need bed in procedure.
Take into consideration many manufacturers claim their pads are performance, but actually it is pile of garbage.
Serious manufacturers like TMD (Textar), Akebono, ATE, etc. don’t require bed in procedure for your every day pad.
 
Soooo.....one of the links above seems to suggest a bed-in procedure can cure a slight vibration problem on newer rotors/pads if they weren't bed-in properly when first installed.

Has anyone actually tried this and had it work?? I was always of the impression that once vibes were there -- even if it is uneven deposition -- you're not getting rid of it without machining the rotors....BUT I've never tried to bed "used" brakes

Also I may be misunderstanding or taking liberties with what the article stated....
 
I bought a vehicle that sat for a while and all 4 rotors had a bit of corrosion under the pads. I replaced the front ones because they were obviously causing vibration. Long story, but the rear ones were also causing a steering wheel vibration. I guess that little bit of braking by the rear wheels was slightly jerking the vehicle. Reading this now it still seems bizarre.
 
Soooo.....one of the links above seems to suggest a bed-in procedure can cure a slight vibration problem on newer rotors/pads if they weren't bed-in properly when first installed.

Has anyone actually tried this and had it work?? I was always of the impression that once vibes were there -- even if it is uneven deposition -- you're not getting rid of it without machining the rotors....BUT I've never tried to bed "used" brakes

Also I may be misunderstanding or taking liberties with what the article stated....
The question is why they were not bed in properly? If everything is assembled properly, there should not be bed in procedure unless we are talking track/race pads.
I take my track pads every time after track day, slap back every day pads I took off before track day and that is it. No vibration etc. But then, I don’t buy junk.
 
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It's not all that easy to find a stretch of road where you can slow down down from 40 to 10 five times then 35 to 5 five more times without people behind you getting road rage.
Agreed. Some service manuals do stipulate a brake bed-in procedure after repair, but it is very "light" compared to some of the ones being posted on the internet. As you said, new cars do not receive any bed-in during PDI and the brakes work fine.

I hear that, but I'm just playing devils advocate here..
For the sake of doing so, or do you actually have something credible to add?

Soooo.....one of the links above seems to suggest a bed-in procedure can cure a slight vibration problem on newer rotors/pads if they weren't bed-in properly when first installed.

Has anyone actually tried this and had it work?? I was always of the impression that once vibes were there -- even if it is uneven deposition -- you're not getting rid of it without machining the rotors....BUT I've never tried to bed "used" brakes

Also I may be misunderstanding or taking liberties with what the article stated....
I have never seen it cure issues. It sometimes makes it worse. IMO, it is because most "ceramic" pads rely on adherent friction and the material is not aggressive enough to clean-off an existing transfer layer.
 
I know they are new rotors, but make sure they are not out of round.

I purchased a set of brand-new AC/Delco rotors put them on the Caprice they were warped right out of the box.
Put different ones on, problem solved.
I had the same problem with some OEM GM rotors for my pickup. I've had new drums come out of the box warped also. My mechanic told me he always turns even new rotors to prevent comebacks...the quality is too spotty.
 
Check to be sure your brakes are releasing when you take your foot off the petal. You probably have swollen hoses to the calipers. Does your vehicle fail to roll immediately after taking your foot off the brake? Does the brakes smell like they are getting hot? Then yep. loosen your bleeders and if your wheel turn significantly easier by hand with the bleeders opened slightly? then yup.
 
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