Brake job, now brakes pull the car left

Unclemeaty

At 35,000 miles I had what seems to be the common vibration fate of the stock 4-pisont sport brake system.

I had the stock rotors turned when the brake shop said they could be, so that saved me a bunch of cash. I used brand new Hawk HPS pads all around, using care and TLC in applying the Hawk included grease to the backs of the pads, shims, and any metal-to-metal touching points, also making sure not to get any of the stuff on the pad itself. With a familiar friend in the garage, we bled all four corners per the factory manual specificaitons (RR / FL, then RL / FR) and added new fluid to the master resevoir after every corner completed. I never let the resevoir level get as low as 'low' always filling it back up to the very top for each corner bled.

The braking vibration has been a thing of the past which was the beast I was initially after.

Now and after about 2000 miles I'm sure the system is fully broken in; the car pulls left under hard braking. Most of the times I also feel the steering wheel try to pull in the left direction, and under a "panic" braking condition I can just about lock up the front left wheel while the front right has less braking power. The last interesting symptom is measured with my IR temperature gun, where the FL rotor will always run about 25% hotter than the FR. The RR runs 25% hotter than the RL.

This weekend I was having to hammer it down for a lot of turns for mountain roads. When the car hunkered down it often wanted to vear toward the center of the road and became quite the choire and just another thing I had to manage and monitor while driving spiritedly.

So far my only trials have been with re-bleading the FR/RL corners thinking there is some kind of air in the lines. I've now bled the lines 3 times to no avail. My next best guess could be something gone foul with the master, or perhaps a flexible brake line got damaged. I've thought of getting aftermarket SS lines but really dont know if that would help or just exaserbate the issue.

Any clues?

TreeSemdyZee

Did you follow any kind of "bedding in" process after you had the job done?

chuckd05

First, check your tire pressure in all of your tires....

if they are good, than chances are you either have a air pocket in your lines, or a caliper seized.. if they worked for 2,000 miles Im willing to bet you may be low on tire pressure...

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Unclemeaty

I did follow the proper bed in with the hawk pads to the t.

the pulling has happend sice the first day out, only its worse and noticable in a real hard situation so 2000miles ive learned to live with it. i was just hoping breakin was still present even after bedin so i gave it 2k. now im tired of the problem.

Stange thing i can do is; if i press the brakes all the way to the floor for a few seconds standing still then take the car for an agressive stop the pulling seems to be better temporarilly.

ive bled the lines of the weaker fr/rl corners four times to no avail.

ChrisSlicks

You bled both sides of the calipers right? It's definitely not the master cylinder as that gives equal pressure to the front brakes, seems as though you have something weird going on with the right front caliper. I would unbolt the caliper and check the pads at this point and look for uneven wear - this telltale sign of a sticking piston (which also would generate the shudder in the first place).

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Unclemeaty

Yup. Outside then inside of each caliper.

To me that seems like a logical step. I'll go ahead and take a look at this later on today. Thanks

SPOHN

I had something similar happen on my truck. Worse at high speeds. I sort of ignored for awhile.

But when I went to fix it, it was defiantly a stuck piston. So if it's pulling to the left it's going to be the caliper on the right with the stuck piston. Well, that was my case. I assume brake systems could play various types of games on you. The pad was wore down to the wear indicators on the left side while the right was hardly wore. Being older truck I just replaced both calipers.

But yea check for uneven wore pads, then bleed hole system again, and check tire pressure.

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ChrisSlicks

For a truck with a floating caliper (what most cars and light trucks have) it would be a stuck caliper slide pin, not a stuck piston. But in this case with sport package the caliper is fixed, base is sliding.

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SPOHN

Oh ok. Same principle I assume.

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ChrisSlicks

More or less, just could have saved yourself a few bucks in that case and just got the slide pins Although sometimes they seize up in the bracket so you have to replace that too (but not the caliper). I've had a stuck piston on my truck calipers a couple of times, you know that is happening because you'll smell burning as the pad drags on the rotor generating a lot of heat. I can usually fix that with a $2 piston seal.

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SPOHN

Yea. But also that same caliper had a burnt look to it. Plus I also get 45% off with my account at O'Railly.

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kenchan

to me sounds like the brakes were not bedded properly due to lack of pressure caused by air bubble in the brake lines.

i would remove all the pads and clean the pad surface using sand paper, bleed the brakes, and re-bed. should work.

Unclemeaty

UPDATE:

Thank you for all the heads up. At this point I think things have gotten slightly better for my brakes but there is still something a bit wrong here.

I took the following steps to help resolve:


1. I broke down the front right caliper but noticed nothing out of the ordinary. All four pistons were able to be pushed in/out by hand without much binding - rules out any caliper siezure. I checked the wear even-ness and rotor for antyhing out of the ordinary but found symetry and evenly worn parts everywhere indicating no binding.

After doing this the problem was still apparent.

2. I bled the rear-left outside then inside followed by the front-right outside then inside calipers. I noticed no trace of airbubbles nor pedal feel changes.

After doing this the problem was still apparent.

3. I got real mad about this whole spiel and stomped on the brakes all the way to the floor with both feet about ~10 times while the car was running by stationary. The funny thing is, this seemed to partially do the trick! its not 100% perfect as the car still drifts slightly left, but its about 75% better than before to the point where I dont get surprised then I press the pedal hard anymore.

Do I maybe have a collapsed or kink in one of the brake lines?

Any thoughts?

Cmike2780

The only thing I can think of that's remotely possible is maybe the brake line needs replacing? Pretty inexpensive part and worth a shot.

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SPOHN

I also wonder if there could still be some air in the ABS module? Seems I remember Reading something of this due to it's hard to get air out of the ABS if it gets in there. Just thinking out loud.

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