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Discussion Starter #1
Front Right Brake Pulsating after the (failed) Alignment by the VW Dealer.

So, I took my car to a VW dealer in South Georgia for alignment after I replaced the control arms. I pulled out of the dealership and noticed a sound reminiscent of a bad strut coming from the front right. I also noticed that the brakes pulsate and the noise got worse.

It was already past 5pm and I had to drive to Atlanta.

Then, I ordered new (reman, original VW) brake calipers from RockAuto. Installed the right caliper. Properly bled using genuine VW fluid. I drove about 30 miles. No noise, nothing. Relieved!

Then, tonight the pulsating and grinding brake noise came back as well as the "bad strut" clunk type of noise.:banghead:

The shocks are new Sachs. Replaced the rubber components as well about 3000 miles ago.
The rotors are new Zimmermann.
The pads are new Ate.
The tire rods new Lemforder.

Although I was able to get my $110 back from the dealer with the help of VW America because they didn't fix the alignment, I didn't think I couldn't make this problem a case with the VW America.

All this started AFTER the dealer. What do you think is happening?

Thoughts appreciated.
 

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Dirty ABS sensor or internally broken wiring to it. When you loosen the TRE for adjustment, you can easily clip the wiring to the ABS. I have not seen any issues previously, but it could happen.
 

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Man you are just having hell o time with this car lately.

By pulsating, do you mean the ABS is activating and pushing your foot back, or is it when you press on the brake you feel vibration being transferred into the brake pedal?
 

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Discussion Starter #5
Man you are just having hell o time with this car lately.

By pulsating, do you mean the ABS is activating and pushing your foot back, or is it when you press on the brake you feel vibration being transferred into the brake pedal?
Thank you Andreas for chiming in. You are valuable to Passatworld! :)

All the problems I have been having are suspension/alignment/control arms etc. related. Thank god the engine is strong and bullet proof.

So, the pulsation occurs whenever I press the brake no matter what the speed is. And, when I press the brake lightly at low speeds, such as 5-10mph, it sounds like rusted door opening. Although, it is very difficult to describe the actual sound here.

I just did vcds scan, there is no ABS fault code but I have read that the pulsation may occur and ABS sensor may be bad without the light being on.

Also, all four wheels show the same speed when the car in motion. So, I assume the speed sensor right above the inner CV axle is fine.

I don't know what the heck that mechanic at the dealer did that caused this!
 

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Just for grins, try disconnecting your ABS module. There are (2) connectors going to the module, disconnect those and then drive the car around the block and see what happens.
If there is change, well then we'll have to isolate that problem.
As far as the strut clunking, if nothing is glaring obvious, it might be the bolts on the top of the strut assembly.
There are (2) points of concern here. you've got the (2) studs that hold the strut assembly to the strut bracket. That is the bracket that the upper control arms are attached to. The other is the whole assembly itself bolts to the strut tower on the car body by the (3) bolts in the triangle pattern in the engine bay. If any of those are loose it makes diagnosing a clunking noise fairly difficult.
 

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as a suggestion pop off wheel, calipers and rotor, make sure all mating surfaces are clean; wheel hub to inside of brake rotor/ outside of brake rotor to inside of wheel/rim, check rotor for marks from a too long lug bolt and brake backing plate if bent.
 

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Did you watch the car at the shop? Maybe they went on a "test drive" and warped the front rotors. I have heard of this happening when I was a teen :)
 

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brake backing plate if bent.
Actually this had happened to me like 8 years ago when I took the car to an idiot guy to replace the CV boot on passenger side. Apparently after he was done with the repair he had not only bent the back plate but also had forgotten to fasten its bolts. I heard intermittent grinding noise until I removed the wheel and discovered his masterpiece.

May be another way to see what is going on is to put the front of the car on jack stands and turn the wheels while someone hits the brake.
 

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I just thought of something...

Did your front lower control arms (the straight ones) get replaced?

If so, there is a remote possibility the wrong size nut is being used to hold the ball joint into the steering knuckle.
Based on your profile info you have a B5 pre-facelift. That indicates to me you have the larger ball joint than what is being used on the B5.5 versions.

This happened to me a few years back when I bought a complete front end refresh kit.
Look at the nut on the left. That was the nut supplied in the 'new' kit. The nut on right is the CORRECT nut.
The nut on the left doesn't make full contact on the back side of the tapered lug the ball joint fits into, causing the flange of the nut to actually slip down into the small side of the tapered hole and cause a very distinct metal clunking noise.

Not saying this is your problem, but you should check. if indeed it is, you'll need the proper nut as this is a potentially dangerous situation.

 

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Discussion Starter #11
Hello all,

Thank you very much for the feedback. Here is the update.

*I removed the sensor and cleaned put it back. Test drove. Same!
*One thing I forgot to mention that I had replaced the sway bar bushings before I took the car to the dealer for the alignment. But, still it didn’t make that noise on the way to the dealer, it started after that.
*Today, I rocked the front of the car up and down and I heard that squeak noise. I will remove the sway bar brackets and test drive the car.
*But, even if it was he sway bar, why the pulsating brakes?
*I think PZ suggested that the backing plate might be bent. I checked it and it is not.
*One of the bolts that holds the bracket is a 22mm, as opposed to the original 18mm. Some dude forced that bolt into the steering knuckle previously. The bracket is tight and not moving at all. I had been driving the car like that with no problem for 10.000 miles.
*Dave has asked me to put some pics. They are attached.





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First I thought this is a dinosaur bone from the Jurassic era :lol:

I hear your puzzle saga drags. The squeaking noise is most probably from the bushings. But the effect on the brakes still amazes me. I would say, make sure the control arms, tie rods, and all other components down under are sitting fit and correct.
 

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Discussion Starter #13
First I thought this is a dinosaur bone from the Jurassic era :lol:

I hear your puzzle saga grags. The squeaking noise is most probably from the bushings. But the effect on the brakes still amazes me. I would say, make sure the control arms, tie rods, and all other components down under are sitting fit and correct.
Thank you for your feedback Emery. It indeed is a dinosaur bone. One from 2003! lol

I am really hoping it just is the sway bar bushings. I will remove the sway bar brackets and do a test drive tomorrow.



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Wow, you got right in there! I didn't expect you to take everything apart.

Well for starters, you've definitely got the right nut on the front lower control arm. That's good.
There is nothing glaring at me that shows anything wrong. I see you've got a brand new axle nut on there. Is tightened down properly? I know it sounds like a rhetorical question, but something somewhere is loose to give you that clunking sound. I'm merely asking to make sure all points of potential opportunity are covered. The axle bolt being tightened down properly is key to the preload on the wheel bearing. The wheel bearing is a double row roller bearing that is designed to be tightened down on it's outside faces, which is exactly what happens when the axle bolt gets torqued down. Does the tire have any play in it when it's off the ground. You'll want to grab the tire at 3 o'clock and 9 o'clock and try to rock the tire back and forth in the direction of the steering movement. And then at 12 o'clock and 6 o'clock and pry back and forth. If the tire/wheel has any movement then the wheel bearing might be compromised. Detecting wheel bearing play needs a keen eye for small amounts of movement. Movement at the (2) previous locations referred by the o'clock positions, can also be tie-rod and or control arm ball joint play. Wheel bearing play is detected by using less force than it takes to detect ball joint play.
Does all that make sense? Want to make sure I'm making things understandable.

I do see some points of concern, but I'm trusting that you are giving true information.
Points of concern:
1) The one I mentioned above with the brand new axle bolt.
2) That one long bolt for the caliper. Just make sure it's not rubbing on the back side of the rotor when tightened down. I see there is a washer on it to take up length so I'm assuming all is good seeing that you mentioned it was good before hand.
3) The bearing flange, the flange face the rotor mates to. It looks pretty crusty and the true mating surface seems to be compromised to have enough surface contact to allow for a true full face contact which in turn makes for a rotor that runs without any runout. That might be where your brake pulsation is coming from. The inside face of the rotor hat (center section of rotor) must have full face contact to the wheel bearing flange face for proper performance. If the rotor runs out more than about a .0015" you'll feel it in the brake pedal.

Still have some un-answered questions though. I know you went through all the trouble to take things apart for the pictures, but, I still would like to see a picture, just with the wheel removed and looking straight down on to the caliper and rotor. I want to see the top portion of the rotor where the brake pads are.
What about the strut itself? Did you check the upper (3) bolts on top of the strut tower inside engine bay to make sure those bolts are tight?
What about the tone ring on the axle shaft? That tone ring must be rock solid around that shaft.
Did you disconnect the ABS unit and test drive the car after that?

To put your mind at ease about that sway bar, the sway bar will not effect the brakes in any way. At least with what were talking about here.
The sway bar may cause a squeaking noise at the rubber mount bushing points. If that's the case, they have a rubber silicone spray that you can shoot the bushing(s) with. Lithium grease works to but silicone is better.
 

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Discussion Starter #15
# Removed the strut. All the bolts, including the 13 mm bracket bolts are right.
#All the control arm bolts and nuts tight.
#CV bolt ok.
#Removed the sway bar brackets. Nothing changed.
#Drove with ABS disconnected. Same!
#The squeak noise comes when I lightly apply the brakes. No noise but pulsation when hard brake.
#Noise comes on occasionally when driving in the highway.
#Attached pictures of the crime scene.



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Damn, you're a go getter. I'm impressed.

Everything in the pictures 'looks' right, except for...
This picture.
That c/v hub looks awfully close to the inside of the steering knuckle. Unless it's an illusion because of camera angle. You should have about 3/32" to 1/8" of clearance all the way around the c/v hub.
Is there any evidence of that hub making contact with the steering knuckle? You'll be looking for any shiny metal surfaces or where the rust is worn away.

 

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Another thing I thought of, with the front tire (problem side) off the ground, use a 4x4 a couple of feet long or a long 2x4 whack the side of the tire, on the rubber only and see if the clunk noise occurs.
 

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Discussion Starter #18
Thank you Dave,

I think the cv axle to steering knuckle contact is a very legitimate concern. I will check it tomorrow.

So, would it cause the squeaky noise lightly braking?

Would adjusting the tie rod tilt the steering knuckle causing it to rub against the outer cv axle? There indeed is no clearance between the two. They are flush.


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So, would it cause the squeaky noise lightly braking?
It's a possibility. Only because after seeing that in the picture I'm suspect of the wheel bearing being bad. If the wheel bearing is indeed bad, it will have radial slop in it, that in turn will cause a cascading effect.
The wheel bearing supports the bearing hub. The bearing hub is pressed into the center of the wheel bearing.
The outer end of the axle shaft (splined end) is supported thru the center of the wheel bearing hub. When the axle bolt is torqued down it essentially makes this whole assembly as one.
So if the wheel bearing has slop in it, the whole assembly is wobbling around inside the steering knuckle. Now take into account the rotor which is mounted to the bearing hub flange.
The rotor being a bigger diameter will magnify the wobbling effect, especially when the brakes are applied, which would definitely give a pulsing in the brake pedal.
During driving all of the rotational forces of the loose bearing are at some happy medium while rolling down the road. Now apply the brakes and all of that gets disrupted.
Long story short, all of this can lead to a squeak, drag, maybe if bad enough imitate a metal on metal worn out brake pad digging into the rotor noise.


Would adjusting the tie rod tilt the steering knuckle causing it to rub against the outer cv axle? There indeed is no clearance between the two. They are flush.
No, for all intensive purposes and for arguments sake adjustment of the tie rod has no effect on the c/v joints/hubs.


The other thing I noticed is you have Marty's Racing Raxles axles. Awesome. You have done well by putting those in. Other than all of the things I mentioned above, we might need to investigate to see if there is a difference in the cv hub dimensions that would cause interference on the backside of the steering knuckle.
I'll tell you what, I'll call Marty at Raxles (he's the owner by the way) tomorrow and I'll discuss that with him and see what he says. I'll then report back to you.

I think we might be on to what is causing your dilema here.
 

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Discussion Starter #20
You are awesome! Thank you very much.
But, the Raxles had 13.000 miles on them before I took the car to the dealer. I had never heard any such noise.

It is something they did at the dealer that caused this.


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