Strange brake/suspension issue (moan/groan from front end)

[Legend_master]

I have a groaning/moaning noise when I am coming to a stop, generally only happens the last 10 to 0 mph of braking (and stops if I let off the brake). I have replaced the rotors, pads, and calipers trying to figure out the noise. I can't seem to narrow it down. All I can think is that there is some bushing vibrating (not in the steering wheel) on the sub frame, but I don't see anything loose, or worn. the noise happens on both the front left, and front right, and happens interdependently on each side. Any gurus out there have any suggestions? The car has all new ball joints (upper & Lower), inner and outer tie rods, and bearings.

[Dr_Snooz]

Do you get the groaning when going over speed bumps?

[Legend_master]

Do you get the groaning when going over speed bumps?

No (unless I'm braking) it only happens when braking at low speeds. I'm going to take apart my radius rod bushings and replace them. I stuck my finger in the drivers side radius bushing, and it felt damaged. I've replaced everything else, its driving me nuts.

[2oodoor]

I can offer some off the wall things Ive run across...
Rotors- directional design? Left and right designation or machined with a directional cut on the lathe.
Dust shields contacting the inside of the rotor down in the narrow close to the center.
Some rotors have dirctional cooling fins but look identical.
Look at pad wear, any favored spots?
Try chamfering the edges of the pads if they aren't already made that way.
Tires yes tires...
How about the dust caps for the hub on the axle side, did you use those or left them off just curious cuz I left mine off.
Have someone else drive the car so you can listen from various positions.
You have a stock suspension more or less now?

[Legend_master]

I can offer some off the wall things Ive run across...
Rotors- directional design? Left and right designation or machined with a directional cut on the lathe.
Dust shields contacting the inside of the rotor down in the narrow close to the center.
Look at pad wear, any favored spots?
Try chamfering the edges of the pads if they aren't already made that way.
Tires yes tires...
How about the dust caps for the hub on the axle side, did you use those or left them off just curious cuz I left mine off.
Have someone else drive the car so you can listen from various positions.


I've gone through 2 completely different sets of calipers, pads, and rotor. All parts were brand new, and with the first set that would make 3 total. Just to narrow out the 11" upgrade I put factory lxi equipment on last. The dust covers are not touching the rotors, I checked this today. You can actually feel the moan/groan in the chassis of the car. I'm gonna try to get a video tomorrow. The only time I've ever heard anything like this was with a car that had worn the pads completely down, and was rubbing metal on metal. Dust caps are installed. Running tokico springs and shocks on the front.

[2oodoor]

Actually feeling the moan/groan used to not be a bad thing lol
Ha, anyhow I guess actually hearing the pitch of the sound knd of helps place it to a part capable of producing it.

[Legend_master]

Actually feeling the moan/groan used to not be a bad thing lol
Ha, anyhow I guess actually hearing the pitch of the sound knd of helps place it to a part capable of producing it.

lol if only that were the case in this instance. The radius rod bushings are on backorder, so I should have an answer come next Tuesday. Another thing I've noticed is a vibration at highway speeds, between 50 an 60, the goes away till 70-75. It does not happen consistently, this is something else that makes me think its the radius rod bushings.

[2oodoor]

Pulling castor in or out according to motion thrust, that makes sense.

[Legend_master]

Replaced the radius rod bushings, now the sound is confined to just the right (both sides before) and much quieter. The bushings did not look damaged at all, but they were much softer then the new ones. The suspension/steering is much stiffer now, and I'm not getting the engine rock I had before. It also eliminated my vibration at highway speeds.

[2oodoor]

I guess now I would temporarily swap front tires right to left. Alignment before that if practical at the time.

[Legend_master]

I guess now I would temporarily swap front tires right to left. Alignment before that if practical at the time.

I'm starting to lean towards the axle or haftshaft. I think the brakes relate just by coincidence, There is a HELL of a lot of vibration coming from the front left above 85mph. Rotating tires did not help the situation.

[stat1K]

could be that one of the cvs is unbalanced. there are just too many moving parts lol... gl man

[Legend_master]

could be that one of the cvs is unbalanced. there are just too many moving parts lol... gl man


I know it is driving me nuts! I have a new axle I need to install, if that does not solve the problem the only thing left will be the haftshaft. I have not been able to find much info on symptoms of a failed haftshaft bearing. I'm hoping it is just the axle, gonna try to get that in today.

[Legend_master]

Axle did not fix the problem with the noise, but did eliminate the vibration at highway speeds. I'm fucking stumped.

[2oodoor]

Wow then there was no one solution for the symptoms! Do you have a spare set of wheels and tires or did you try that?
You're getting close, at least you got the shaking part, that would bug me the worse.

[Legend_master]

Wow then there was no one solution for the symptoms! Do you have a spare set of wheels and tires or did you try that?
You're getting close, at least you got the shaking part, that would bug me the worse.

had the tires rotated and balanced today, and I have tried a different set of rims and tires. I found that there is a slight leak from my brake master cylinder onto my brake booster. Do you think either of those failing could cause a noise?

[ShyBoyCA6]

Can we get a video?

[Rendon LX-i]

A vid would be nice. Seems to be it can be a tire issue. Low pro tires tend to soak up a whole a lot of noise. I had customers with 22-24 inch wheels then I swapped them to the original tires an took away the noise . Try to put some stockies to see if you confine the noise.

[Legend_master]

Can we get a video?

I'm working on that.


A vid would be nice. Seems to be it can be a tire issue. Low pro tires tend to soak up a whole a lot of noise. I had customers with 22-24 inch wheels then I swapped them to the original tires an took away the noise . Try to put some stockies to see if you confine the noise.

Definitely not the tires, I'm not even running low pros as well as multiple sets of rims. Plus the fact that it only happens when brakes are applied. I'm thinking maybe one of the sub frame bushings are shot. I just don't want to take them off to find out there is nothing wrong.

[Rendon LX-i]

sounds like that could be a issue.

[Legend_master]

So now that it is warmer outside I am not able to re-create the noise. I have taken a movie with audio of the area. Does not look like the rear subframe is moving. I am going to check the front next.


http://www.youtube.com/watch?v=6icDnkbLyXo&feature=youtu.be

[Legend_master]

Alright, I captured it on film. The noise can be heard clearly at 1:03 right after a metal pop. Then you can hear it faintly at right before I come to a stop every other time. It is much louder in the car which make me think it might be somewhere on the firewall. You can hear it for a stretch from 2:29 to 2:34 as well.


http://www.youtube.com/watch?v=ir9lXgPoBIQ&feature=youtu.be

[2oodoor]

Damifino but that was great lol, I need to play it on the tv so I can get the freqency of it... Weird is right. Kinda a worn spline sound but the scrape click roar is strange.
Does it matter if you're stopping with clutch pushed in or left in gear, any gear and approach the stop?

[Legend_master]

Damifino but that was great lol, I need to play it on the tv so I can get the freqency of it... Weird is right. Kinda a worn spline sound but the scrape click roar is strange.
Does it matter if you're stopping with clutch pushed in or left in gear, any gear and approach the stop?

Well its always clutched due to the fact that only happens right as I'm about to stop. You can't hear it, but the moan happens longer after you hear it. All the way till I stop completely, the camera just can't pick it up. The metal pop was new, never heard that before lol. Brand new axle, and exactly the same noise with the old axle. I'm gonna put camera near the brake booster and see if the noise is louder.

[Oldblueaccord]

Try checking the torque of the bolts that the radius arms goto the LCA or spray them with wd 40 and see if it helps.

[ShyBoyCA6]

doesn't sound lubricated enough to me. did you have this with the other engine in it? B18 or A20? what about the inner bolt for the lower control arm? is it torqued to spec? Also by the sound of it and the only place i know that could possibly make that sound is the front crossmember i could be wrong but there is a washer type thing that holds the bushing in place. The name slips my mind -_- it could be slightly lose to make the noise. great vids btw always wonder how things moved down there when your driving and holy shit is there alot of moving parts hahah.

[2oodoor]

I know right, the pinch fork looks like rubber, and the bolt looks loose. Optical illusion.
The roar reminds me of input bearing/shaft noise, so did the clank now that I think of it ...on domestic trucks though.

[Legend_master]

I may check out unbolting the lower arm, lubing, and re-installing the lower control arm. That is one thing that I have not removed (since it has poly bushings). As far as before the swap; I have no idea, this car has only been driven once with a a20 by me lol.

[Rendon LX-i]

To me the pop sound is a axle but the other pop sounds like a strut rod or bushing problem . Btw awesome vid

[Legend_master]

To me the pop sound is a axle but the other pop sounds like a strut rod or bushing problem . Btw awesome vid


That pop was some random occurrence, not fully sure. I'm gonna do some more vids, I'm interested in what the back looks like while moving lol.

[Oldblueaccord]

That pop was some random occurrence, not fully sure. I'm gonna do some more vids, I'm interested in what the back looks like while moving lol.

Ok I think now maybe I hear the brake pad rattle clips. They might be catching the rotor edge.

The other bad thing is a bad bearing or a snapring floating around.

[Legend_master]

Alright I'm really leaning towards the brake booster as the failure. For one I have developed an idle haunt issue that I can alleviate by pumping the brake pedal. I went through all the procedures in the manual to check it, but they all came out ok. The noise now happens even when not moving when the idle surges. Here is a video, you can hear it clearly at 51 seconds and every time the idle comes down until I release the brake and start moving. I'm thinking the diaphragm inside the booster is what's making the noise.


http://www.youtube.com/watch?v=wi09T0yrAXY

[Hauntd ca3]

disconnect and plug the booster vac hose and see if that gets rid of the noise and idle fault.
had a funny idle problem with an old car, disconnected the booster, no more problem apart from hard as brakes