MarcyproJe

I know these pops and clunks in our cars has been covered many times. I have tried every single thing I can think of, and everything I have read. I've owned this car for 4 months, and I have spent 3 out of the 4 working on solidifying the front of this car.

Basically, when coming to a stop using good pressure on the brakes, I get an audible pop as I slow down to a stop. Sound is coming from drivers side. I start off forward again, it pops again slightly as if something is going back into place. the car drives fine otherwise as I have replaced and repaired everything else. If I go slightly lighter on the brakes to slow down with just moderate pressure applied, no pop? Ill run down the list of items I have addressed since owning this car. Can anyone think of anything else that might cause this? Is it related to the pressure applied by the brakes and not related to suspension?

Repairs done so far:
Rotors and pads - front and rear. front pads were replaced twice
New front brake pad hardware
New Caliper Pins with fresh grease
Swapped front drivers caliper
New front struts
New front sway bar bushings
New front sway bar links (ordered, installed this weekend)
Replaced broken front sway bar brackets and bolts (bought car with this damage)
New Lower Control Arm Bushings (PSB Polyurethane)
New Steering Rack Bushings
New Inner Tie Rods
New Outer Tie Rods
New Ball Joint (drivers side)
New Front tires and Wheels
Alignment and Tire Balance

STREETGS

motor mounts

kevin3344

I second that.

I replaced my motor mounts (and transmission mount) last year, and I could feel a vibration as I accelerated past 2,000-2,200 RPM. No clunks mind you, but the vibration was pretty noticeable. See if you feel anything as you accelerate. It should smooth out around 3,000 RPM. Once I had those done it drove like new.

MarcyproJe

No vibrations to speak of really at all. Not sure on the condition of the motor mounts but i guess i never considered it. Do you all think that normal braking would cause a bad motor mount to clunk? The sound feels like metal on metal coming from the drivers side. Maybe ill get in there and check the bolts at least. I once had a car with motor moubts that were not tightened well. Still though, vibrated but did not give a hard clunk.

lyonkster

One thing I didn't see in your list is the No 2 lower control arm, how are those looking?

Other than that, is the noise a pop or a clunk? I just fixed my popping noise, which I differentiate from a clunk as being very sharp and short, as opposed to the thud/clunk sound. Not very helpful, I know. In my case, after replacing a bunch of suspension parts unnecessarily, it ended up being the brakes. It was a bit different than your situation in that the noise only occurred once every time the direction of travel was changed.

So I'd back out of the driveway, and when I tapped the brakes, I heard the pop. Then I'd put it in drive and it would pop again when I hit the brakes the first time, but never again. Until I put it in reverse, then the whole scenario repeated.

I replaced the rotors (they had some cracks that I didn't like the looks of), as well as the pad hardware. The pop went away completely, even though I am not sure what exactly fixed the issue. I did notice that there are several ways to install the pad hardware in the calipers, and I didn't know what the "right" way was (the service manual was of no use). I do know that I installed them differently than they were installed before, to put the compliant part of the clip on the back rather than the front part of the caliper. I don't know if that's what made the difference, but I do know that the pop is gone now.

Not sure this will help you, but this was my experience.

kevin3344

You didn't mention your mileage, but if you're over 150,000 miles you might want to look at your engine mounts there is one on each side. While you're there it's usually worth it to do the transmission mount since it's probably worn as well. You mentioned you did the ball joint on the drivers side...I would replace the one on the passenger side just to be safe. Reason being just because it sounds like it's on the driver side it could be originating from the passenger side so keep that in mind.

JLAWS

From your profile I see that you have a GS300 so motor mounts should be as hard to replace. Gs400/430 are a pain in the ***. If they have never been changed then it's definitely time

Most of the time visually you can't see how bad the mounts are until you take them off. For both Gs400 and 430 I've owned, the mounts were split in half. Your engine is probably moving around when you start and stop. A quick way to check the mounts is to open the hood and put the car in drive while holding the brake give it gas. Do the same in reverse. If you see a lot of movement then it is the mounts. Good mounts will only make the engine tilt left and right slightly. Go with oem Lexus mounts

lyonkster

I replaced motor mounts on my GS430 at about 90K, but I never had problems with clunking with the old mounts. Rather it was vibration being transmitted into the interior when the car was idling.

I don't quite see how bad motor mounts would clunk due to braking. I can potentially envision a clunk when accelerating, but not when braking.

kphu

iTrader: (8)

odd...I have the same exact type of issue. I just completed the front end suspension rebuild:

strut
strut mount
outer tie rod
lower ball joint
sway bar link
lower suspension arm no 2
rotors
brake pads

I literally just got the car back on the road on monday and started noticing it yesterday.

Arcadian

Upper arms. mine started with the odd 'pop' under braking. It gets as bad as sounding like popcorn when braking on a rough road. Diagnosed by dealer BTW.

MarcyproJe

Upper arms were on my list. The main issue i have is reproducing the sound so i can actually pin point it. I can only get it going when braking at speed or if i let the car roll and slam on the brakes. Cant find it with the car in the air no mattet how much i tug and pull. Im still confused because it occurs so in sync with the brakes. Maybe i will swap my front rotors from left to right and see if that helps. There is also potential for play there.

MarcyproJe

Im the 4th owner of the car, currently 179k. The car was fairly well sorted mechanically and kept clean.

JLAWS

Go to https://secure.drivers.lexus.com/lex...-lexus/home.do and register your car to see the service history. See if you can find history of the motor mount being replaced.

You've almost spent what the car is currently worth

kevin3344

+1 for the dealer. A little more expensive but they know the car better than anyone. They helped diagnose my lower control arm issue a while back. OP it sounds as if you're getting engine movement under hard braking, which is why you can't find any play in your suspension components. I would take it in and have them diagnose it. Could be easier in the long run.

kphu

iTrader: (8)

I was thinking the same thing...I put new rotors on...if the rotors doesn't sit in the grove of the hub then it's possible there is a little bit of play?