suspension or brakes issue?

[PSHUMARD1]

Hello prime was looking for some suggestions to a problem I have. Every since I had my 99 Terra when I go over a speed hump or a somewhat significant bump I get a clunk sound from front of car I have searched and haven't found a similar sounding problem. The thing that's odd is if I have the brakes applied I don't get a clunk. I just installed BC coil covers and its not them I purchased sos steering bushings but don't think that will solve it. This is probably the worst thing about the car so I guess I lucky but it makes it feel cheap so would really like to fix. Thanks for any and all help.

 

[docjohn]

what sway bar?

 

[nsxtasy]

What's a "99 Terra"?

 

[USAFguy22]

floating caliper?

 

[PSHUMARD1]

Factory sways. I meant targa. OK I never heard of floating caliper so what would the fix be? Thanks for the input

 

[USAFguy22]

I meant floating rotors, typical in many aftermarket brake systems (not sure about yours) where the disk has some movement inside the caliper and is not mounted solidly to the hub. This reduces the chances of thermal distortion (warping).

 

[TURBO2GO]

I meant floating rotors, typical in many aftermarket brake systems (not sure about yours) where the disk has some movement inside the caliper and is not mounted solidly to the hub. This reduces the chances of thermal distortion (warping).

Floating rotors aren't actually "floating" they are simply not a one piece cast alloy, but two pieces secured together by a dozen nuts and bolts. They don't wobble, and they wouldn't be making that noise. Sounds like he has either a loose caliper or a bad sway bar end link. An inspection would yield more answers than guesses here, along with a video, or more info as to if its one side or two, when it started, what speeds it happens at, etc. Hearing it on a video would help but this is probably nothing a mechanic can't find in 5 minutes with the car on a lift.

 

[PSHUMARD1]

I think I ask the shop to see if they can find when I take it to get the steering bushings installed but thanks to all for the input from everyone.

 

[USAFguy22]

Floating rotors aren't actually "floating" they are simply not a one piece cast alloy, but two pieces secured together by a dozen nuts and bolts. They don't wobble, and they wouldn't be making that noise. Sounds like he has either a loose caliper or a bad sway bar end link. An inspection would yield more answers than guesses here, along with a video, or more info as to if its one side or two, when it started, what speeds it happens at, etc. Hearing it on a video would help but this is probably nothing a mechanic can't find in 5 minutes with the car on a lift.

Ah I stand corrected then? My mind was applying motorcycle knowledge to cars

 

[02#154]

Floating rotors aren't actually "floating" they are simply not a one piece cast alloy, but two pieces secured together by a dozen nuts and bolts. They don't wobble, and they wouldn't be making that noise. Sounds like he has either a loose caliper or a bad sway bar end link. An inspection would yield more answers than guesses here, along with a video, or more info as to if its one side or two, when it started, what speeds it happens at, etc. Hearing it on a video would help but this is probably nothing a mechanic can't find in 5 minutes with the car on a lift.

Are you sure about all that? I agree that the sound the OP is hearing is probably not the brakes, and that a tech would likely find the fault pretty quickly.

But a lot of the better two-piece rotors ARE floating type for the purpose mentioned by USAFguy22. This type of rotor does tend to rattle. The Brembo rep at NSXPO 2003 held a rotor in his hand and wiggled the rotor while holding the hat firmly and you could hear the rattling fasteners.

Also, the literature oline for the StopTech Aerorotors plainly states that they are floating rotors.

SOS lists a "race only" option for the StopTechs that does not come with anti-rattle fasteners.

J

 

[TURBO2GO]

Are you sure about all that? I agree that the sound the OP is hearing is probably not the brakes, and that a tech would likely find the fault pretty quickly.

But a lot of the better two-piece rotors ARE floating type for the purpose mentioned by USAFguy22. This type of rotor does tend to rattle. The Brembo rep at NSXPO 2003 held a rotor in his hand and wiggled the rotor while holding the hat firmly and you could hear the rattling fasteners.

Also, the literature oline for the StopTech Aerorotors plainly states that they are floating rotors.

SOS lists a "race only" option for the StopTechs that does not come with anti-rattle fasteners.

J

I was sure, but now you are throwing doubt into my mind. I have never seen rotors that were actually "loose" on the hat by design. Now this is turning into a trivia question. I know my stoptech kit is not. I've never seen a rotor that was. But perhaps you saw something I have never seen.

 

[nsxtasy]

I was sure, but now you are throwing doubt into my mind. I have never seen rotors that were actually "loose" on the hat by design. Now this is turning into a trivia question. I know my stoptech kit is not. I've never seen a rotor that was. But perhaps you saw something I have never seen.

My Stoptech aerorotors were the same; the hardware was always snug, never rattling.

 

[docjohn]

my brembo indy rotors don't rattle and are snug to the "hat"

 

[TURBO2GO]

I don't see how you can have anything remotely "loose” with the forces that are exerted on the disc. I mean you are stopping the weight of the car. If anything is remotely loose the hats are going to sheer off the rotors and then you are in some serious trouble.

I think the term "floating" is just misunderstood and taken too literally. All it means is that it is not cast out of the same piece of metal as a single piece. They are still attached to each other with a lot of force. But creating multiple points of attachment instead of a solid piece helps with heat dissipation.

 

[Stephen@NCAutoUSA]

It may be a suspension issue. I've had numerous front end noises throughout the years with other cars and things. Ones that come to mind was I had some type of wire hanging looking pin not put back on one side of my vw brake pads before so it had a high pitched clank when going over bumps. On the Nsx I had a clunk noise due to my suspension at one time. Never figured out what that noise was. I can hardly hear anything inside my cabin sometimes.

 

[silver2002]

Do you have a lower chasis bar installed [as a modification]? That can clank on the sway if something else is off.
The Lower Chasis bar can be seen running close and parallel to sway, infront of spare tire, above battery tray, if you have one.

 

[02#154]

If you thighten the rings so tight onto the hats that they cant move, then what youve created is effectively a fixed rotor. Floating rotors need to move relative to each other.

References are hard to find, but i found a few...

http://www.zeckhausen.com/Brembo/Rotor_Replacement.htm

http://youtu.be/bldL1M87PrQ

http://www.vehiclecraft.com/Brakes/rot_ques.htm

http://forums.corvetteforum.com/c6-z06-discussion/2979815-clicking-noise-stoptech-rotor.html

http://www.automotiveforums.com/t953251-can_you_quot_jiggle_quot_your_rotor_on_the_rotor_hat_.html

Lots more examples about this on motorcycles. Not as much about the issue on cars.

I've personally R/R rings on hats and every other fastener rattled. This was on a Brembo "Indy" front BBK

I'm sure you guys have the StopTechs that SOS sells with the anti-rattle fasteners.

J

Point of clarification: it's the fasteners that "rattle", not as much the rotor.

 

[docjohn]

my screws are torqued by hand to 5 ft/lbs as per larry B....no rattles.

 

[nsxtasy]

If you thighten the rings so tight onto the hats that they cant move, then what youve created is effectively a fixed rotor. Floating rotors need to move relative to each other.

They need to move, but not easily - and nowhere near easily enough to rattle. Stoptech uses special fastening hardware (made of an alloy called iconel) that permits movement as the outer ring expands and contracts, but not at any other time.

 

[PSHUMARD1]

No, i dont hav e any other added sway bars or the like just what came from the factory. I did take it to a local shop but he didnt have time to get into it much but im hopefully taking it back this coming saturday when he installs the SOS steering bushing kit and can find the problem for me.

 

[Rope]

Was the suspension adjusted properly with the preset set on the springs with the 2 upper nuts and the hieght set with only the lower nut?

 

[illwillem]

Check the strut to hat tightness, then strut to chassis tightness. If those are loose it'll cause more of a deeper clunk, a lot of times aren't tightened enough if air tools weren't used when they were assembled off of the car. To fix it like this; With the car on the ground with the wheels on (compressing the suspension) you can put a 14mm socket on the top nut of the coilover that is visible when you pop the hood tighten it if it turns that was likely your problem. After than maybe wheel bearings. Basically you can check everything at once jack of the car and support it with a jack stand. Leave the wheel on. Grab it with your hands at the 12 and 6 oclock position then the 9-3 o'clock position and forcefully rock it back and forth, if you hear a click or a clack if its probably the wheel bearing. Ball joints is similar but take a bit more force. Grab the wheel both hands at the 6 o'clock position and shake in and out and forward and back do the same at 12 o'clock and watch for movement in the to make move but you should be able to feel play. For end links you can wrap the sway bar in electrical tape or painters tape and listen for a change in the tone of the clunk, after a bit check the tape for scuffing or marks indicating where it may be rubbing.

 

[PSHUMARD1]

Yes the coilovers where pre loaded and the clunk noise was there before i installed the coilovers.illwillem, i will ask my mechanic to try this if he cant figure it out and thanks for everyone input.

 

[NYCNSX]

Is the sound you are hearing kind of like a metallic ping? A metal on metal sound that wouldn't be described as a clunk and more of a rattle when the two pieces of metal come into contact with each other?

 

[PSHUMARD1]

No metal on metal sound