BayAreaLex

Sam the car was driving me bonkers today with the clunking!

I ordered rubber top hats to replace the solid pillow ball top hats on my Megan LP coilovers. Hopefully that will quite things a bit. Regarding the brake springs:

Driver top:


Driver bottom:


Passenger top:


Passenger bottom:


I also noticed that my front dust shields are awfully close to my rotors. I will bend them back the next time I am in there:

Blanco

iTrader: (8)

Were you ever able to locate a torque spec table? I'm about to do some more front end work, and want to check all the nuts to eliminate possible clunking sources.

sam12345

iTrader: (1)

It looks like the springs are correct. Did you check both sides? (inner pads)

BayAreaLex

Thanks for the confirmation Sam. I have not yet checked both sides but will soon.

This weekend I plan to replace my POS Megan LP top hats (pillow-ball) with Megan EZ rubber top hats to quiet the damn thing down. My pillow ***** are worn and sound like a popcorn machine going over bumps.

I will never again run a solid pillow ball type mount on the street unless I am prepared to replace them every 5-10K miles.

BayAreaLex

Sam, for the clunking up front, I am suspecting the sway bar bushings, as I've indicated previously.

Think it would make any sense to remove the sway bar completely for a mile to two to isolate it?

GS714

Just a suggestion. Get a silicone grease and spray it on every rubber joints. Since you just dropped it. I think its maybe the UCA banging against the frame. maybe.

sam12345

iTrader: (1)

Those sway bar bushings are so cheap just change them

BayAreaLex

I doubt that it's the UCA hitting the strut tower. The reason is that I hear the noise mostly over uneven surfaces (low amplitude but high frequency road imperfections). It also did it before the coilovers when the car was a good 1.5" higher. Additionally, on the highway when I hit a huge high amplitude dip I don't hear anything, so I'm rulling out the UCA (at least the part about the UCA banging something. It may very well still be UCA bushing/joint related).

All noticeable clunks are low speed clunks where they are mostly noticeable over uneven surfaced but not necessarily huge dips where the suspension compresses the most (that's where you would expect the UCA to tag the strut tower)

Agreed, but I was thinking more for the reasons of isolating the problem. I guess if I replaced them and the problem is still there, it's pretty good indication that it's not the sway bar bushings. inspecting the stock sway bar bushings doesn't show any obvious wear or damage, but that doesn't mean they aren't the culprit.

Case and point, my ball joints/tie rod ends never had any play, but I replaced them anyway, and it had a huge effect on my steering vibration problem and overall road feel...

goodyonsen

iTrader: (1)

I have been wondering about this as a cause for some of the weird noises i get from my front suspension, i have megan LPs as well. Have you got around to doing this? Results?

Thanks

BayAreaLex

Goodyonsen,

I plan to swap this weekend. And don't worry about the results as I am 100% sure it will address the problem I am trying to address because if I can clearly hear the pop corn popping noises coming from the top of the coilover.

I've said it dozens of times and I will say it again. For a street car, the EZ top hats are the only way to go.

BayAreaLex

Sam, I think I may be onto something...

Today, I parked my car on a steep downward hill. I started the car and I heard a groaning. It was a groaning that I would expect to be coming from the brakes. But the car wasn't moving and the sound didn't change between having my foot on and off the brake. I back the car up to flat ground and the sound went away. I then went rolled into the steep downhill and the sound came back.

I have no idea what is actually making that sound, but it's got me thinking that maybe my motor mounts are shot and that's what's actually causing the clunking and not anything in the front suspension. Also, I have noticed that when I mash the gas from a stand still, I get a minor jerk.

It's possible that the clunk, the groan, and the jerk are all related to the mounts.

I will have to dig deeper but this might be my problem.

jtwags

I believe I have the same exact issue as BayAreaLex on my 2002 sc430. I have replaced balljoints, tie rods, caster arms, brakes and steering rack bushings. I have no vibrations, shakes, etc… but I have that darn low speed clunking when traveling at low speeds (less than 20mph) over uneven/rough surfaces. No sounds or problems at higher speeds. I have inspected the sway bar bushings and torqued the brackets. I am at a loss as well. I guess it could be the sway bar bushings but they seem to be in good shape and everything is tight. I am really curious to see what the final solution is as I am tired of replacing parts and getting the “I don’t know” look from the mechanics.

BayAreaLex

Jtwags,

What you describe is exactly my own symptoms and funny how we've replaced exactly the same things. I also inspected my sway bar bushings and they *looked* to be in great shape.

I am betting its one of the following:

Sway bar bushings
Sway bar mounts loose
Motor/tranny mount

Lets keep eachother updated on the progress.

Luke

sam12345

iTrader: (1)

Well, not sure if it's motor mounts but that is easy to check. While someone else is in the car with the brakes on and in gear look at the motor mounts while they gas the engine. You will see the motor lift off the mount (look at the driver's side mount). The motor mounts are a well known weakness after a 100k or so

https://www.clublexus.com/forums/perf...or-mounts.html

https://www.clublexus.com/forums/2gen...-bushings.html

https://www.clublexus.com/forums/susp...or-mounts.html

https://www.clublexus.com/forums/gs-s...or-mounts.html

https://www.clublexus.com/forums/gs-s...braking-2.html
D
https://www.clublexus.com/forums/gs-s...front-end.html

BayAreaLex

Will do Sam.

Also found today that my rear brakes were missing the plate at the top of the caliper that puts tension on the pads and keeps them from moving. I'm sure that didn't help with the quiet ride. Luckily my local parts chain had the rear hardware kit in stock and I was able to correct the issue.

Rubber top hats were installed today in the rear as well. I'm hoping my rears are quiet now.

Assuming no surprises, I'll be moving on to the front soon.

EDIT1: And I took my brother's 90k mile 2003 540i for a spin yesterday. The front end felt so tight and buttery smooth. Made me envious!

EDIT2: I've put about 50 miles on the car since installing the rubber top hats in the rear. I can confirm that the rear is quieter than it was but not cured unfortunately. I'm going to replace the rear endlinks ($16 from Rockauto) and the sway bar bushings ($10 from Rockauto) for good measure and hopefully be done with the rear for good.