Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
Click here to visit TireRack
Brakes & Suspension Forum sponsored by The Tire Rack

Losing traction? Need new tires?
Click here to visit the NASIOC Upgrade Garage...
Go Back   NASIOC > NASIOC Technical > Brakes, Steering & Suspension

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 10-08-2005, 11:27 PM   #1
sajohnson
Scooby Specialist
 
Member#: 6140
Join Date: Apr 2001
Chapter/Region: MAIC
Location: Middletown, MD, USA
Vehicle:
2002 WRX 5MT Sedan
WR Blue. Cobb Stage 2

Unhappy Clunk in front end since Prodrive & KYB Install

For the most part I think switching to KYB GR2 struts and Prodrive springs all around has been a big improvement. One thing bothers me though -- when the springs/struts reach close to full extension, I hear a noticeable 'clunk' sound.

I've done a search, checked hardware as recommended, and everything is tight. The only thing I noticed is that with the front end raised (suspension unloaded) the springs are not at all compressed -- I can rotate them a bit in the spring perches by hand. This is the only thing I can think of that may be causing this noise.

The rears have rubber between the springs and top and bottom perches, but the fronts only have the rubber on top -- the bottom is metal on metal.

Anyone else with this setup notice this?

Is there any easy fix -- compressing the spring and slipping some rubber hose over the lower spring coil for example)?
sajohnson is offline   Reply With Quote
Old 10-09-2005, 12:46 PM   #2
gc822
*** Banned ***
 
Member#: 81217
Join Date: Feb 2005
Chapter/Region: Tri-State
Default

Quote:
Originally Posted by sajohnson
For the most part I think switching to KYB GR2 struts and Prodrive springs all around has been a big improvement. One thing bothers me though -- when the springs/struts reach close to full extension, I hear a noticeable 'clunk' sound.



Anyone else with this setup notice this?

Is there any easy fix -- compressing the spring and slipping some rubber hose over the lower spring coil for example)?
the first thing I thought of was the bumpstop being hit... also, is everything installed correctly??

AFAIK, Prodrives are designed to work with an OEM strut with no mod
gc822 is offline   Reply With Quote
Old 10-09-2005, 03:23 PM   #3
sajohnson
Scooby Specialist
 
Member#: 6140
Join Date: Apr 2001
Chapter/Region: MAIC
Location: Middletown, MD, USA
Vehicle:
2002 WRX 5MT Sedan
WR Blue. Cobb Stage 2

Default

Quote:
Originally Posted by gc822
the first thing I thought of was the bumpstop being hit... also, is everything installed correctly??

AFAIK, Prodrives are designed to work with an OEM strut with no mod
That is my understanding as well. I know many people have this setup and apparently _don't_ have this problem -- so I could have made a mistake. Still, I'm an electro/mechanical tech by trade and the R&R seemed pretty straight-forward to me. No leftover parts!

I can say that it definitely is not the bump stops -- it is a metal on metal 'clunk' -- as if something is shifting.

I still have the front end up in the air. Everything is tight except the springs. They aren't about to slip off their perches, but I am able to rotate them a couple inches without using much force.
sajohnson is offline   Reply With Quote
Old 10-09-2005, 01:10 PM   #4
advanracing62
Scooby Specialist
 
Member#: 61899
Join Date: May 2004
Chapter/Region: NWIC
Default

tighten the top strut bolt- it's not tight enough... that's where I'll put my money.
advanracing62 is offline   Reply With Quote
Old 10-09-2005, 03:28 PM   #5
sajohnson
Scooby Specialist
 
Member#: 6140
Join Date: Apr 2001
Chapter/Region: MAIC
Location: Middletown, MD, USA
Vehicle:
2002 WRX 5MT Sedan
WR Blue. Cobb Stage 2

Default

Quote:
Originally Posted by advanracing62
tighten the top strut bolt- it's not tight enough... that's where I'll put my money.
That's possible. They're tight, but only as tight as I could get them with my extremely professional 'vice-grip + 19 mm socket' method. I couldn't use a torque wrench because the shafts would spin, so I used the vice-grips which allowed me to put a hex wrench thru the socket to hold the shaft in place.

I've heard people say to use an impact wrench. I have one, but that worries me because then I would have no way of knowing how tight they are.

Any ideas?
sajohnson is offline   Reply With Quote
Old 10-10-2005, 01:21 AM   #6
sajohnson
Scooby Specialist
 
Member#: 6140
Join Date: Apr 2001
Chapter/Region: MAIC
Location: Middletown, MD, USA
Vehicle:
2002 WRX 5MT Sedan
WR Blue. Cobb Stage 2

Default

In one of the threads I read thru before starting this one...

http://forums.nasioc.com/forums/show...4&page=7&pp=30

...Scotty recommended using LPS2 spray lube on the strut shafts to prevent the clunking sound. Anyone try this? Are there other sprays that work as well or better?

Of course, even if this were to solve the problem, it would be temporary and I would think it would just be treating the symptom.
sajohnson is offline   Reply With Quote
Old 10-10-2005, 03:42 AM   #7
Arnie
Scooby Guru
 
Member#: 1725
Join Date: Jun 2000
Chapter/Region: International
Location: Germany
Vehicle:
2002 Subaru Forester
SG silver

Default

did you compress the front springs when installing them? prodrive springs are a bit trickier to install because its hard to get the spring compressors on and still be able to compress the spring enought to fully expose the threads of the spigot. At the most, I can usually only get two coils clamped ( you need to evenly clamp coils on both sides or you compress the spring unevenly). Even then, I need to press down on the hat in order to get the nut started as the spring isn't really compressed enough. There is a little lip on the spigot that the hat usually catches on and you might think things are snug but they are not. I always use an electric impact to tighten down the strut tops and just reach my hand in to hold the shaft to keep it from rotating. You can tell from the tone of the impacts that the nut is fully seated. I have one of those Sears supposed 200 lb0ft or torque impact wrenches. It has nowhere near that. After over 70 suspension installs, I have yet to hear any complaints of knocking from the strut tops or damaged strut internals not the strut spigot. Also, make sure you have the upper spring perch properly oriented.

Seriously, most noises coming from newly installed parts are usually because of faulty installs. Nice that you are an engineer but that doesn't necessarily mean you can properly install suspension. Believe me, there are enough subtleties in a suspension install that can lead to noise, improper alignment and lots of frustration.
Arnie is offline   Reply With Quote
Old 10-10-2005, 04:15 AM   #8
sajohnson
Scooby Specialist
 
Member#: 6140
Join Date: Apr 2001
Chapter/Region: MAIC
Location: Middletown, MD, USA
Vehicle:
2002 WRX 5MT Sedan
WR Blue. Cobb Stage 2

Default

Thanks Arnie, maybe I'll try the impact wrench.

BTW, I never claimed to be an engineer -- I only have an associates' degree -- but in my work as a train control tech I work on all sorts of electrical and mechanical equipment. In addition, I have worked on cars (as a hobby) for about 30 years. My experience is spotty though, for example, I have rebuilt engines but never a transmission. All I meant to imply was that I do have a clue.

I was able to compress the springs all the way. In fact, I remember thinking that I had made extra work for myself by compressing them a little further than I had to. The tops went on easily and I tried to make sure that they were seated on the 'shoulder' below the threads on top of the spigot. I tightened the nuts down before releasing the compressor and everything seemed snug. Still, as I said above, I could have made a mistake.

The only part of your post that wasn't clear to me was the following sentence:

"After over 70 suspension installs, I have yet to hear any complaints of knocking from the strut tops or damaged strut internals not the strut spigot."

I don't understand what you mean by, "...not the strut spigot."? I'm probably just being dense, but could you rephrase that sentence?

Finally, in your experience, is it normal for Prodrive springs to be loose enough that they can be turned a few inches CW/CCW when the suspension is unloaded?

Thanks!
sajohnson is offline   Reply With Quote
Old 10-10-2005, 04:29 AM   #9
Arnie
Scooby Guru
 
Member#: 1725
Join Date: Jun 2000
Chapter/Region: International
Location: Germany
Vehicle:
2002 Subaru Forester
SG silver

Default

My bad on using the word engineer! Not trying to insult your experience, I've just seen enough people who have loads of car experience make little mistakes that are particular to this suspension and scratch their heads!

Anyway, regarding the spigot...I'm trying to say that you shouldn't have to worry about shearing off the threaded portion of your strut with your electric impact wrench. I've installed quite a few with an impact wrench and not once have I damaged that threaded portion. I suppose if you keep hammering away, you'll eventually break it off but if you listened to that change in tone when the nut cinches down, piece of cake.

Its been a few months since my last prodrive install, but I never noticed the springs being particularly loose in the perches, at least not so much that i could twist them a couple of inches. i could ask a buddy with Prodrive springs to jack up the front of his car to see if the springs are snug.

Well, it sounds like you got the springs compressed enough and made sure the upper spring perch was safely beyond the shoulder. That's good. did you orient the upper spring perch correctly? I've also seen a few upper spring perches rotated 180 degrees opposite from where they are supposed to be. Lots of knocking there. Hmm, did you remember to put the rubber insulator between the spring and upper spring perch? What about the orientation of the dome washer? Is that on correctly? did you cut your springs?!?!? Just kidding.

don't worry man, we'll figure this out!
Arnie is offline   Reply With Quote
Old 10-10-2005, 04:33 AM   #10
Arnie
Scooby Guru
 
Member#: 1725
Join Date: Jun 2000
Chapter/Region: International
Location: Germany
Vehicle:
2002 Subaru Forester
SG silver

Default

oh, BTW, when you say "when the strut reaches close to full extension you hear a clunk" what situation is this in? flying over railroad tracks or dropping off of big dips or what?
Arnie is offline   Reply With Quote
Old 10-10-2005, 10:50 AM   #11
Uncle Scotty
*** Banned ***
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK buy Nates beans
westcoastroasting.com

Default

.....do you have the strut upper perches 'pointing' in the right direction????

the holes gotta be oriented properly...

Uncle Scotty is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Clunking in front end, high milage 2.5RS TheIglu Newbies & FAQs 8 11-24-2009 10:25 PM
clunking in front strut assembly after spring install (only when car turns) Damon Brakes, Steering & Suspension 9 10-15-2007 06:12 PM
clunk in rear end???? subeman90 Baja Forum 4 09-27-2006 06:26 AM
Clunk in front end flent Normally Aspirated Powertrain 13 08-13-2002 12:20 AM
Clunking from front end SubieFL Brakes, Steering & Suspension 25 10-29-2000 03:01 PM

All times are GMT -4. The time now is 12:20 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.