JDMV8

iTrader: (6)

Hey guys.

I've been trying to diagnose a strange tapping noise from the front end. It occurs at low speeds <10mph, and is heard almost 100% of the time when slowing down from 5-0mph, particularly when applying the brakes--the brakes seem to be crucial in making the noise. I can also hear it sometimes when turning after a stop. I never hear the noise at speed while braking or turning, etc. I recorded the noise from outside of the car by pumping the brakes repeatedly when coming to a stop (attached).



What I've done:
New pads
New caliper hardware (pins, shims, etc)
Resurfaced rotors and retorqued the hat bolts (girodisc 2 piece--all was torqued good to begin with)
New lower balljoints (Moog--greased liberally)
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Upper balljoint is good--all bushings except the front most in the LCA (which is in fine shape) are spherical and relatively new. The wheels do not shake or move or make any noise when I lift the car in the air. Wheel bearings good on both sides. Wheels are balanced. Brakes are bedded in. Outer tie rods are relatively new.

At this point I'm thinking inner tie rods (probably not--steering feels good and alignment is constant) or calipers need a rebuild? Something may be loose?

If anyone else has had a similar noise, please do give your insight, thanks!

LeX2K

Can you duplicate the noise by kneeing the bumper as to make the car go up and down?

JDMV8

iTrader: (6)

No. It only occurs during almost at a 100% rate when braking at low speeds <5mph or 50% of the time when turning the car at or almost at full lock at 0-5mph with no brakes applied.

LeX2K

Raise both front wheels and try to duplicate the problem that way you'll know if suspension related or what rotates. Could be a bad axle.

JDMV8

iTrader: (6)

I did raise the front end and steered the car with no wheels on--no noises unfortunately (fortunately?) And raised each wheel individually and there was a slight movement at 3-6 o clock until I replaced the lower ball joints and tie rod ball joints. Wheels are solid after that but the noise is exactly the same as it's always been.

LeX2K

Can you duplicate the sound car in park rocking the car fore/aft? I don't recognize that sound meaning have not heard it on any car I've worked on closest I had was a screeeeeeee sound from a failing axle. Hopefully someone smarter than me knows.

MMI

@dannyk1113 had a similar noise recently posted here https://www.clublexus.com/forums/is-...ow-speeds.html
Not sure if he ever figured it out but I had a similar noise a while back and it turned out to be due to the radiator support bracket/reinforcement bar had some missing/loose bolts. If you can't figure it out I would suggest getting the dealer to use chassis ears to narrow it down. I had several mechanics scratching their heads trying to figure it out until dealer took half hour using chassis ears to locate the source.

lobuxracer

iTrader: (2)

Retorque all the nuts and bolts in the front suspension. I had a similar noise at similar speeds and found it was the tie rod ball joint nut. Check ALL the bolts and nuts on the front suspension.

JDMV8

iTrader: (6)

Unfortunately no. I tried recreating it in as many ways as I could so far.

Do I access these bolts from taking off the front bumper, under the hood, or looking underneath? Because I did not find anything notable underneath.

I changed balljoints on both sides and torqued to spec with new hardware. Noise stayed the same.

lakai5

Hard to tell from the video but sound like it could be the pads shifting, I just had this issue yesterday, I heard it when going over bumps and sometimes releasing the brakes like you...

I double checked everything, only thing I noticed were the pads had some movement to them and sounded like my noise, only on the driver side which was weird...

So I ended up bending the top metal bracket thing that presses on the brake pads, not sure what its called but I circled it in the pic below...

I just bent it the opposite way a little to create more force on the pads and that stopped them from shifting around and fixed my noise

MMI

Just checked my invoice, yes they did have to take the bumper off to access. It was 6 bolts on the front radiator reinforcement bar.

JDMV8

iTrader: (6)

Actually, not a bad idea! I'll try that. I actually bent my old one a bit which felt flimsy and I replaced them and the pins and the 14mm bolt. You could still move the pads a bit with the new hardware, but they move less although the sound is exactly the same. I'll try bending this thing to oblivion.


Thanks so much! I will check these bolts soon if this problem doesn't go away. Also good idea regarding the chassis ears.

JDMV8

iTrader: (6)

So it seems the issue is the metal bracket that pushes the pads into place. I flipped its orientation 90 degrees and felt the pads moved more and then took the car for a drive: way more of the same chattering was occurring. I guess I'll try bending it...strange to have to do this as this is completely new brake hardware and new ferrodo ds2500 pads.

JDMV8

iTrader: (6)

I bent the brake pad bracket against the pads and greased the pins and shims. The pads have almost no movement in the calipers when I move them by hand. Compared to before, you could easily wiggle the pads. However, the noise still persists. I always hear it braking downhill and usually hear it on a flat surface. Don't notice it during uphill braking though. I still don't hear it when braking from any speed >20mph and I don't hear it on bumpy roads unless I'm applying the brakes. I still think it's brake related.

lakai5

Definitely sounds like brake pads shifting, did a quick google search for ferrodo pad issues, and seems like this is a common issue with these pads amongst all car types, a lot of people complaining about clunking...

I've had this issue on my ct200 that the pads would shift/clunk when going from forward to reverse, but they eventually settled and no more noise, maybe they will wear in over time or maybe try some different front pads?