The most common cause of vibration under braking is uneven transfer of pad material onto the discs, either from poor quality parts or from improperly bedding in the new parts.

Are you using OEM pads and rotors?
Did you drive conservatively for the first 100 miles with the new parts? Hard driving/hard use of brand new brakes, and especially then coming to a complete stop while the rotors are still hot, can cause too much pad material to be deposited in one spot. That will case a LOT of vibration when applying the brakes.

Once things are bedded in this no longer is a concern, but with new parts it is an important thing.

If you suspect it was the bedding in process you can sometimes recover the parts by doing a very exaggerated bedding process (you find a LONG road with no traffic and do several very hard brakings from high speed to moderate speed, in a row, to really heat up the rotors and while doing so, the pad material will be embedded more evenly onto the rotor surface, and then drive for as long as possible without stopping, until the rotors are able to cool down. There are guides how to do this on the internet, "Bedding in new brakes".


One other thing to consider is if the rotors could have been put on with some rust/corrosion between them and the bearing hub. A rotor that has runout because of foreign material holding it out can cause vibration as it pushes the pads in each rotation, under braking.

 

In more than 40years working on disk brakes, I've never seen a pad leave any kind of deposit onto a rotor. That defies science to imagine such a thing happens. Brake pad friction material wears down into dust, not sticky transfer. Rust will rub off, and unless there's a serious pitting situation, it will rub off evenly. Show me an example, because I need to learn how this is possible.

 

Note that this pad transfer to the rotor is something that came along after the removal of asbestos.

Most of the time no one even notices it happens, but if you take a car with brand new brakes and go driving it like a hooligan getting them super hot on the first day, the result will be an awful lot of pulsing under braking. I was amazed at how much I'd messed things up when I'd done that. Did some research and found a lot of internet "how to" guides about the matter. Did the "heavy re-bedding process" on a long country road and it helped repair my mistake.

 

Did you clean the hub face when the rotors were being replaced? If not, the rust and other dirt stuck on the hub will cause the new rotor to sit unevenly, and you'll get the "warped rotors" feeling within a few days of installing new rotors.

 

With the front end up on jack stands and the rear wheels blocked / park brake engaged, let the car idle in 1st gear, and check for any runout of the front tires or bends in the rim

 

The hub flange is clean with no rust and no debris under the rotor. I did embed the brakes before. The parts are from O'Reilly's. I'm thinking possibly the hub/wheel bearing might be bad. But I don't hear any noises at all.

Possibly a bent rim as I have hit pot holes in the past. I'll rotate the tires and see if that changes anything. I'll jack up the front and put the car in 1st gear and see if there's any wobble.

 

A bent hub is rare but definitely possible, esp if you had pothole encounters. Internal damage to the tire is also possible, though damage to rim or tire would typically be present all the time and not just under breaking. Rotating wheels front to back should answer that question.

You can get a cheap dial indicator at Harbor Freight or online and measure the hub and then rotor runout. Anything more than 2-3 thou on the hub (without rotor), or 5-6 thou on the outside of the rotor would indicate bent hub or uneven rotor.
Be careful when measuring the rotor runout - it is best to have a flange bolted and torqued to imitate the wheel pressing the rotor to the hub. I have used a big wheel spacer in the past for this. Otherwise, the rotor can move around and give you a bad reading.

Bad wheel bearing is possible in theory, but I haven't seen that cause braking vibration on these cars.

 

Are the caliper pins sticking? How are the control arm bushings? The lower ball joints and tie rod ends?

 

No, the pins aren't sticking, the control arm bushings are good along with the lower ball joints and tie rod ends

I rotated the tires and no change at all, it's still the same as before. Now I'm going to inspect the hub.

 

Check the CV joints. A stiff joint can cause a vibration that increases with speed, from about 40-80....independant from braking.

 

How do I check for a stiff joint?

I checked hub and I put the car in drive and there's a slight wobble. I spun the hub by hand and it's not that smooth at all. Can this be caused by a stiff joint?

I plan on replacing the entire steering knuckle assembly. I looked at Rock Auto and there are a few selections. Are all three brands about the same quality? I'm assuming none are made in USA or Japan but made in China. Moog used to be good back then but now it's all made in China. Has anyone here used any of the three brands below?

 

How do I check for a stiff joint?

I checked hub and I put the car in drive and there's a slight wobble. I spun the hub by hand and it's not that smooth at all. Can this be caused by a stiff joint?

I plan on replacing the entire steering knuckle assembly. I looked at Rock Auto and there are a few selections. Are all three brands about the same quality? I'm assuming none are made in USA or Japan but made in China. Moog used to be good back then but now it's all made in China. Has anyone here used any of the three brands below?
View attachment 453771 View attachment 453772

Check for a stiff joint by disconnecting axle from the hub then flexing the joints on it by hand. If it isstiff in any direction, the joint is bad. Replacing the axle is a remedy for that.

 

I had a similar issue with my 2008 Camry. I sandblasted my caliper bracket and hub, among other things. 20,000 miles since and no vibrations. More info at the link below.

https://www.toyotanation.com/posts/14895252/