Vibration when braking, HELP!!!

[doobycareful]

I have major vibration on my 99 NT when I break on the highway, my steering wheel shakes. It also vibrates at lower speeds only when breaking, I can feel a pulse in the pedal and after I drive for a while and the breaks heat up I can hear a noise comeing from the back passenger wheel its like a squeek then pause then squeek and its simultanious with the pulse of the break pedal. I have changed my front rotors and pads and rear pads, but it still shakes. As for the back I only changed my pads. Can you please help its very annoying especially in sumer time(cause the wheels get hot faster). Thanks to all.

 

[jrjackso]

when you changed the pads and rotors, did you properly bleed the brakes. does the pedal feel mushy or does it feel stiff.

 

[doobycareful]

when you changed the pads and rotors, did you properly bleed the brakes. does the pedal feel mushy or does it feel stiff.

The pedal feels pretty soft and then twoards the end it gets hard. This could have something to do with it?

 

[romeen]

If it only does it when braking then the rotors are probably warped. You can either replace them or have the existing ones turned.

 

[doobycareful]

I just got new ones like 3 months ago.

 

[romeen]

In your initial post you stated that you did not replace the rear rotors. Furthermore there is a rhythmic squeaking which consistently coincides with the pulsing in the brake pedal. Unless I misunderstood you it sounds like the rear rotors (or at least the right rear) is warped.

 

[doobycareful]

In your initial post you stated that you did not replace the rear rotors. Furthermore there is a rhythmic squeaking which consistently coincides with the pulsing in the brake pedal. Unless I misunderstood you it sounds like the rear rotors (or at least the right rear) is warped.

But do you think that rear rotor can cause my whole car and steering wheel to vibrate? you are right the rear rotors aren't replaced.

 

[Defiant]

Check for a bent wheel, and blown steering components. What kind/size wheels are you running?

 

[doobycareful]

16" How do I check for bent wheel?

 

[romeen]

Any tire shop should be able to check it for you. One other thing you can try is in a safe place get the car up to about 30-40 mph. Then GENTLY pull up on your e-brake and see if this reproduces the vibrations. If it does the rear rotors are probably warped. Remember, do this in a safe manner and don't get too aggressive with the e-brake.

 

[Doug99RS]

Don't rule out poorly machined rotors from your parts supplier. Where did you get them from? Also, if it's been three months it's possible that you've warped them already.

 

[Superbeast406]

Any time you have a brake vibration you need to thouroughly inspect, or have a mechanic inspect your brakes. I am a mechanic, and being so I can ocassionly get ignorant about the condition of my own car. I had a vibration a few months back and shrugged it off as warped rotors seeing as thats the most common cause. I figured I'd fix it when I get time. Almost two weeks later when I was about to turn the rotors I found a very obvious crack in one of them. Cracks are very bad, I could have shattered the rotor if I had to do a panic stop. Not to scare you or anything but get it checked out as soon as possible! A proper diagnosis is hard to make over the internet.

 

[mitsured420]

Dont rule out your front rotors either i work in a brake shop i see new rotors out of the box that are warped.Romeen stated a very good way to test for front and rear pulsution.To check your steering and wheel bearings just lift the weight off the tire and try to wiggle it,side to side and up and down.Side to side its probly your tie rods or rack,up and down your looking at a wheel bearing.sound to me like the fronts need to be machined i would do the rears also just to be sure

 

[doobycareful]

Side to side its probly your tie rods or rack

I just got a new AC/Power Steering belt installed and I wiggled the front wheel and it moved side to side, quite a bit. So where is my tie rod or rack and how do I relace them??? Thanks for the help

 

[staticbrainwash]

It may not necessarily be warped rotors, it could also be a good deal of lateral runout in the rotors.

Cheap rotors do this a lot, and especially cheap rotors on newer cars.

 

[doobycareful]

where is the tie rod or rack and how do I relace it???

 

[staticbrainwash]

Pick up a haynes manual man. You can get them at autozone or advanceauto or most parts stores. That will tell you all you need to know. OR get a shop manual cd. They're like 35 bucks on FP's site.

 

[xXaTaXx]

Not meaning to jack the thread but I have a similar problem and don't want to start another thread just for someone to go unhappy on me.

There are a few different instances in which this problem likes to arise, and from what I've deduced, they all seem to be inter-related. To make this easy on the eyes, I'll break each case down.

[número uno]
Most times during moderate daily driving, I--regardless of braking pattern or conditions--expereience small 'chirps' from my front-left rotor the instant I touch my pedal. Said 'chirps' happen only as I touch the pedal, they are not continuous and have no efect on pedal pressure / steering.

[número dos]
When a warm day comes around or when I need to use my brakes a bit more heavily, the situation changes from 'chirping' to more of an all-out squeal. The squeal dosent always happen but definately often enough to worry about.
NOTE: still referring to the front-left rotor

[número tres]
On the highway or at high(er) speeds --If a situation presents itself where I must either panic-stop or just use my breaks heavily, my steering wheel vibrates, along with the brake pedal itself but, no squeaking. Coinciding with this occurence (but only on high-mid/hard stops), I hear a tap/clank from the front-right that sounds like it comes from something hitting the chassis/underside of the car almost but, I'm not sure. Sometimes it happens more then once, sometimes not. It also dosen't seem to be road condition related, it just happens.


Finally, a FYI: I have never changed my rotors, and I really dount doubt that I need to. I have a slight alignment problem that does not affect driving, but I know this because the inside of my front tires is worn noticibly moreso than the outside. I have changed my front pads though-- ceramic pads. These problems didn't go away then either. Any help would be reatly appreciated! Thanks!


Chris.

 

[Doug99RS]

Not meaning to jack the thread but I have a similar problem and don't want to start another thread just for someone to go unhappy on me.

There are a few different instances in which this problem likes to arise, and from what I've deduced, they all seem to be inter-related. To make this easy on the eyes, I'll break each case down.

[número uno]
Most times during moderate daily driving, I--regardless of braking pattern or conditions--expereience small 'chirps' from my front-left rotor the instant I touch my pedal. Said 'chirps' happen only as I touch the pedal, they are not continuous and have no efect on pedal pressure / steering.

[número dos]
When a warm day comes around or when I need to use my brakes a bit more heavily, the situation changes from 'chirping' to more of an all-out squeal. The squeal dosent always happen but definately often enough to worry about.
NOTE: still referring to the front-left rotor

You may want to inspect the brake pad hardware and put antisieze on the caliper brackets where the pads rest and slide in the brackets. This could account for a "chirp" like noise when you initially apply the brakes lightly because the pads move towards the rotors without actually clamping very hard (strictly proportional to your foot effort).

Also, there is an adhesive spray Carquest sells you can put on the back of the brake pads that will help keep the pads stuck to the caliper. What this does is makes sure that the pad fully disengages from the rotor when you release the brakes and also helps reduce brake noise and a little bit of dust.

Slide grease is also important on the caliper pins/bolts to make sure that the calipers are moving freely and are not binding up anywhere along the way. This will help promote even inner and out brake pad wear as well as prevent your pins from rusting up. Do not use wheel bearing grease, get brake caliper grease from the parts store.

[número tres]
On the highway or at high(er) speeds --If a situation presents itself where I must either panic-stop or just use my breaks heavily, my steering wheel vibrates, along with the brake pedal itself but, no squeaking. Coinciding with this occurence (but only on high-mid/hard stops), I hear a tap/clank from the front-right that sounds like it comes from something hitting the chassis/underside of the car almost but, I'm not sure. Sometimes it happens more then once, sometimes not. It also dosen't seem to be road condition related, it just happens.

Sounds like you've got rotor pulsation and possibly a caliper bracket or caliper bolt loose. Also, the lubricants and adhesives MIGHT help with these noises as well. If you have a 2g don't forget about the lower lateral arm recall and the possibility of a bad ball joint on the straight lower control arm.

Finally, a FYI: I have never changed my rotors, and I really dount doubt that I need to. I have a slight alignment problem that does not affect driving, but I know this because the inside of my front tires is worn noticibly moreso than the outside. I have changed my front pads though-- ceramic pads. These problems didn't go away then either. Any help would be reatly appreciated! Thanks!
Chris.

Rotors are commonly overlooked items when it comes to a brake job. Most people look at them and think if there's no heavy grooves in them then there's no need to do anything with them. What they don't realize is that a worn rotor will have thickness variations that you cannot see without the use of a dial indicator that will only get worse the more you drive it. This will cause rotor pulsation. In addition to that, you've got a brand new flat brake pad that is being forced in to an uneven surface of a rotor. This will promote a brake squeel at some point in the cars life and not resurfacing the rotor will increase the chances of the pads making noise.

Ceremics are good because they will disperse heat better but I think you'll still need to check your bolts, ball joints and make sure you've got the lubricants and adhesives in the right spots.
D

 

[xXaTaXx]

Thank you!
I also wanted to ask about the tire wear though. For illustration purposes,
car- [====] -curb
If I were to pull my two front tires(I haven't checked my rear), they would look like such: (x indicates almost NO tread whatsoever) .
car- [x===] -curb
I know replacing my tires is nessecary but, I'd rather fix the problem (if exists) beforehand.
The car hasn't been in an accident that I know of, but it has been in a low-impact collision w/ a curb (rashed ### my F/L rim) after our most recent abrupt snowfall. Other than that, no alignment problems. Has me confused.

Thanks again!
Chris.

 

[doobycareful]

Dont rule out your front rotors either i work in a brake shop i see new rotors out of the box that are warped.Romeen stated a very good way to test for front and rear pulsution.To check your steering and wheel bearings just lift the weight off the tire and try to wiggle it,side to side and up and down.Side to side its probly your tie rods or rack,up and down your looking at a wheel bearing.sound to me like the fronts need to be machined i would do the rears also just to be sure

For the tie rods which ones do I need to replace? innter or outer?

u steal my post shame on you J/K

 

[Doug99RS]

Thank you!
I also wanted to ask about the tire wear though. For illustration purposes,
car- [====] -curb
If I were to pull my two front tires(I haven't checked my rear), they would look like such: (x indicates almost NO tread whatsoever) .
car- [x===] -curb
I know replacing my tires is nessecary but, I'd rather fix the problem (if exists) beforehand.
The car hasn't been in an accident that I know of, but it has been in a low-impact collision w/ a curb (rashed ### my F/L rim) after our most recent abrupt snowfall. Other than that, no alignment problems. Has me confused.

Thanks again!
Chris.

Well, it depends on how the tire wear started because toe and camber can both start in the same spot.
http://dsmtuners.com/forums/showthread.php?t=144245&highlight=tire+wear
Check out that thread and then you might get a better understanding as to how some tire wear starts. Camber will usually be on the inside like you're showing but will evenly wear down the section you've pointed out. Toe on the other hand will still wear out that same section only it will create a high and low spot in the tread kind of like wedges, shown as the yellow triangles in that thread, as the tread wears.

As for which tie rod to replace, you'll have to diagnose which one has the movement in it by holding the wheel/tire at the 3 and 9 o'clock position and move it side to side. If you have a bad tie rod end then you will feel slop in the movement prior to actually moving the entire steering gear assembly. When you feel the slop ending and the resistance of the gear starting, stop forcing the wheel to move in that direction and reverse it. Do this back and forth so that you're only making the movement happen in the slop range. From there you can put your hand on the inner and outer tie rod ends and determine which of the two has the most movement in it and replace it accordingly.
Doug

 

[doobycareful]

I checked both front tires and the passenger side moves side to side a good amount but I checked the driver side and it moves a little but nowhere near as much as the passenger side. So is it ok if the wheel moves a little (side to side) or if it dose the tie rod is bad? Thanks