MonkikiX

Alrighty, well no updates to this thread yet so I'll expand a little. I've gotten underneath my GS400 with a prybar and checked for any movement without luck. I did notice the rear passenger caliper is very close to the rotor on the outside face. I'm wondering if a slightly warped rotor would cause the same noise. Other than that, possible something to do with the differential or loose emergency brake hardware? Anyone come across a cause/solution to this issue?

ChampGS3

iTrader: (6)

I first talked about this issue back in 2010 and I had been ignoring these noises for a while but now that its warm outside and I have been riding with the windows down it is driving me crazy again. I had a few things that were loose, such as I needed to secure the bumper cover just behind the rear wheels where a push clip had come out and there was some rattle but that didn't fix the other rattling we are dealing with.

From everything I have found this is Not a suspension related sound at least on my car. Others have talked about struts and upper washers etc. being the culprit but this is not the case on my car as I have carefully installed my KYB/Eibachs with all new OEM rubber bushings and everything is torqued down well. Also when parked any pushing down on the rear or jumping inside the trunk produces no amount of noise aside from some tire squeak from the garage floor.

I am beginning to think that is must be with what Mike 813 said about the exhaust heat shields or the parking brake hardware? It is now more pronounced on the drivers side on my car but that could be because I am listening out of the drivers window? The only time I hear this is over quick oscillations over lightly broken pavement or pothole type stuff.
Could something above the Y pipe heat shield area, maybe a transmission plug or harness or shifter linkage be making this? I would think this would produce noise more toward the center of the car. I even thought about the trunk vents in the side rear bumper area that open/close when air enters/leaves the cabin. I have heard them venting but its more of a plastic sound and the one we are chasings is more light metal?

We gotta keep this alive until this is solved as we all have this problem. I love my car and it otherwise rides/handles excellent but this noise really makes the Lexus seem old / aged.
Sorry for the long post.

ChampGS3

iTrader: (6)

https://www.clublexus.com/forums/sus...cement-11.html

Could we be chasing this lower spindle/hub bushing noise? Post 159 page 12? mentions rattling? I really don't think so as I had my rear jack up a few days ago and couldn't get any play by grabbing the wheels at 12/6, 9/3 or any other combination. Who knows???

Ideas? Solutions?

98sleeper

I think i narrowed it down. There's a street around my job where the pavement is so pot holed that it's almost like cobblestones. People always look and they're like "that can't be the Lexus sounding like that?". I noticed that when i'm on the brakes, the noise completely goes away over the bumps. I've even lightly engaged the brakes and pressed the gas going down the street and the noise went away. Sooooooo, I think it's the brake pads rattling in their cages.

I've looked at everything else and tapped everything else and nothing made a noise as close to the rattle as a brake pad hitting the caliper (think jingling inside the cage). If it were some kind of ferrous alloy then the noise would be more "ringy" than "rattly". Like hitting an aluminum pipe versus an iron pipe. I'm going to inspect the little spring that is supposed to hold the pads apart when you're off the brakes and see if that fixes it. here's hoping.....

MonkikiX

That makes sense. Mine is he same exact thing. Press the brakes a tad and it goes away. I tried to jiggle the shims or whatever I can reach without pulling the caliper without luck but if the pads have any room inside, or the spring like you said, that would be a similar sound.

Johnny Rad

https://www.clublexus.com/forums/sus...me-define.html

Same damn thing for me ... mine is 90% fixed. Three different times I had the techs under my car crowbaring evyerthing in sight to no avail until they really, really pulled on the caliper.

ChampGS3

iTrader: (6)

I see what you all are saying regarding this "rear brake" noise...I get the same noise in a quiet parking garage and it is more like the pad is touching the rotor in an uneven manner. It goes....skurrrt.............skurrrt..........skurrrt......but as soon as I touch the brakes the sound goes away. I attributed this to the pads in the caliper "cage" not totally sitting parrallel to the rotor. From what I remember I don't think the rear pads have the V-shaped seperator springs like the fronts do so the rear pads are left to kindof find there own resting place once brake pressure is released.

However the noise that I am still getting is unrelated to the brakes and is the other clangy / rattling noise I get over bumpy pavement. I understand that it is possible that this could be other members issues but mine is not. I still suspect something in the general rear subframe and suspension area.

Does anyone know what the sound is like, that others are getting from the lower spherical hub bushing in the other thread that I posted about?

MonkikiX

Hmm I'm not sure about that other noise then again our clanging noise could be caused by more than one thing or once we find it and fix it, we come across another.

ChampGS3

iTrader: (6)

EDIT, I must apologize as it looks like I spoke too soon. It does seem like the rattle is coming from the brakes. As many have said when going over the bumps/irregularities if the brakes are applied the noise Completely goes away!

I am ordering a rear hardware/fitment kit asap and I am running oem pads so I think this should solve my noise. I will be very happy if this fixes this issue but if not, at least when I hear the noise I will know it isn't some part of my car that is ready to fall apart.

ChampGS3

iTrader: (6)

The rear brake "fit kit" did the trick. The little springs that seperate the pads are the main solution. No More Noise at all from my car all for less than $10 from Rockauto.

MonkikiX

Good to know. I'll have to try that. Thanks!

98sleeper

Awesome find. I'm going to look up that kit right now!

I found one close to me. This link may help you guys as well:

http://www.autozone.com/autozone/par...er=102434_0_0_

Thanks to Sewell Lexus:
http://lexus.sewellparts.com/images/...000/470903.jpg

http://lexus.sewellparts.com/accesso...1998/2858.html

98sleeper

Ordered! Well, the OEM kit lasted 14 yrs....why not buy OEM again. Got a great CL discount at Sewell as well :-)

394LEXUS

the V shaped spreader srings on the rear pads were non-existent on my 00 gs300. replaced the pads and used all new hardware and problem is now gone. it was pretty irritatiing

thecody

I am having the same problem when accelerate slowly some times it makes the "rattling" noise, seems to come from the exhaust area. But when I really accelerate is goes away, what could attribute to this problem? Going to look in the other comments but I do not think mine involves the brakes.