Ok so a routine brake job turns into........

[demarpaint]

Interesting, these pads had no shims, the pads I used before did. I did spray them, but now wonder why they didn't have shims. They were an exact matchm just a different brand.

I'm going to drive it around today and see if anything changes, I seriously doubt it. I might pull the right front rotor and swap it with the old rotor, and see if the condition improves. If it does then the rotor is warped. I'm not sure what the odds of two rotors being warped is but that is also a possibility.

I introduced 3 variables here, pads, rotors, and bearings. I'm pretty sure I can rule out the pads and bearings.

 

[demarpaint]

I just took it for a test run of about 8-10 miles, and did some nice aggressive stops. It seems to be improving compared to the thumping I had yesterday. This has me a bit puzzled.

Maybe I got a little grease on the pads, although I doubt it. Or maybe the cleaning of the new rotors wasn't as good as it should be? Or maybe I still have a problem, with a warped rotor?

I want to drive it about 100 miles and see what happens before I start screwing around with this thing again.

Is it possible it needs a little more miles to properly bed these new brakes?

Thanks for all the replies!

 

[demarpaint]

I just spoke to a buddy of mine who was a BMW tech years ago. He said they always cut new rotors before installing them. I did an economy brake job, I treated the old Aerostar to new rotors, but didn't want to be bothered cutting them. My buddy said it could take 500 miles for things to settle down, he'd give it a little time before he started taking things apart. I'm going to give it a little more time.

 

[mechtech2]

OK.
We have to take a look.

Jack her up and take a wheel off. Use the lugs [maybe with spacers or washers] to seat the rotor lightly. check any suspected corners.
Spin it and see if you feel a pulsation.
There is not much there - A rotor of wheel bearing causes rotational thumping.

 

[demarpaint]

Thanks Mechtech2. The Aerostar is RWD, so the rotor stays in place when the wheel comes off. There is no play at all in the rotor, the bearings are seated properly. Everything spins nicely, thumping comes when brakes are applied. Now with about 40 miles on it it has improved somewhat.

I honestly believe these cheap rotors (Wearever) are 1. Slightly warped, although I can't detect it by spinning the wheels, or 2. They need a little time as my friend had suggested to bed and wear in a little.

Worst case is I go back to AAP and tell them I'm not happy with the parts and get replacement brakes and rotors and do the job over again.

Again thanks for the replies!

 

[KilgoreBass]

Originally Posted By: demarpaint
I just spoke to a buddy of mine who was a BMW tech years ago. He said they always cut new rotors before installing them. I did an economy brake job, I treated the old Aerostar to new rotors, but didn't want to be bothered cutting them. My buddy said it could take 500 miles for things to settle down, he'd give it a little time before he started taking things apart. I'm going to give it a little more time.


I think it depends on the rotor, the ones I bought at Auto Zone specifically said they did not need to be cut, I guess they are pre-machined or something. No problems at all with them. Also, I thought one of the reasons us DIYers buy new rotors was to avoid the need to cut?

BTW, even a cheap dial indicator should show any warpage that would cause an issue. It's a good tool to have, and would eliminate one of your variables.

 

[demarpaint]

The rotors shouldn't have to be cut, which is why I didn't cut them. But I'm wondering if that would have helped in this case? The condition seems to be improving, we've logged about 100 miles on it since the change. There is a slight pulse in the brake pedal if you apply them hard, but not as bad as the first time out.

I'm going to give it a little more time, and if need be change the pads and rotors again. I contacted AAP and they said they stand behind the product and will replace the pads and rotors if need be. I don't have a dial indicator, that would certainly help in this case.

 

[mechtech2]

You can try and roughen up the rotors by evenly sanding them. By hand or any type of sander. 150 grit or so.
Then note if there is a change concerning pulsation.
What we are trying to do is see what part are the problem.
Be warned, the first few brakes that you attempt will not be great.

 

[demarpaint]

Thanks, here is where I'm at with this. I called AAP and complained, they were actually quite helpful. They offered replacement rotors and brake pads. I really don't feel like doing the job again and wanted to give it some time.

What I did notice is the pulsing at higher speeds is not as bad. It seems it is worst at about 30 mph. Slight touch of the pedal it is non existent, before it was noticeable even at the slight touch. I've logged about 125 miles since the brake job.

I'll give it till Monday if it doesn't improve I'll return the parts and start over.

 

[demarpaint]

I drove the car for about 350 miles total and decided the situation wasn't going to get better. I changed out both front rotors, problem solved. I knew the second I stepped on the brake after completing the job the first time that the situation wasn't going to get better, but hope and denial are very powerful I guess. I'll get to the rear brakes shortly.

Thanks again for all the replies!

 

[Vikas]

Did you also changed the brand of rotors?

 

[demarpaint]

Originally Posted By: Vikas
Did you also changed the brand of rotors?


No, I was after price. You do really get what you pay for, but in this case, beater car, I didn't care. The other issue was availability. These rotors were the only ones that they could get locally from one of their other stores. If it were for my Jeep, or E-150 I would have ordered premium parts online.

It's all good now!

 

[babyjay8495]

Happy you were able to get it fixed. It's a pain to do a job right and turns out the parts are bad right out of the box. I am still wondering if being cheap rotors had anything to do with it. I workedin autozone a few years ago while in college and the only difference between the cheap brands and the expensive brands was the box. Maybe one was made in Northern China and the other one was Southern China, who knows. But i do remember that we had limited space for all the rots we had and many times we stored them on the sides instead of laying flat, which i have been told can affect the rotor. I wonder if something similar could have happened to your rotors.

 

[demarpaint]

I think it could have been in the handling of the rotors. Stacking them on pallets can cause problems. A buddy ordered Hawk parts IIRC and had a bad rotor, it happens.

The main thing in all of this was AAP was very helpful, after a little quizzing that is. Once they realized I knew more than they did it was very easy getting exactly what I wanted which included new bearings and grease seals as well.