I have a set of HKS Hypermax RS coilover, and the rear are making clunking noises. I talked to someone who works at a subie shop and he said that that is typical of the Hypermax coilovers...that the rear clunks only on the WRX and no other cars---so no matter what you do or how you tune the coilovers, you will get the clunking noises from the rear struts. Just wanted to confirm if anyone else is having the same issue with this particular coilover. thanks.

someone's got to know something about these...hmmm?

did you fix the prob?? cause im running hipermax RS as well and im getting that annoying sound as well...it happens at low speed when my car goes over small minor dips, it makes the clunking sound i believe when the spring/strut is compressing...help someone!

Clunking noises are normal on coilover suspension. If you're still in doubt take off the rear and make sure it's assembled correctly. The nut washer etc etc

I am running Hipermax IIs and started getting "the clunk" toward the end of last summer. It only happened at low speeds over small bumps in the road and only if the temperature was around 80+. I spoke with a tech at HKS Kansai Service, and he recommended that I send them in for an overhaul, which runs about $125 per strut. HKS USA should have a service depot also.

Tunable coilover suspension isn't the "install it and forget it" application that most people are used to. They require constant maintanance to stay in proper working order. Having them overhauled (seals, bushings and oil changed) every couple years is normal. They may need rebuilt more often depending on how much abuse they are forced to withstand. In my case, I have had these struts for almost 2 years, they are used on the track often, and the roads that I have to drive on daily are about as smooth as cobblestone. Its about time to send them in. Hope this helps.

http://www.hks-power.co.jp/products/suspension/hipermax/

Go to this page and click on the button with the wrench icon for more info.

Forgot to mention that I have a GC8 STi, and the clunking is ONLY in the front. The rear is fine.

Mang, yeah i spoke with a tech rep at Racing Dynamics or something like that and he contacted HKS down in Socal and they quoted me about $200 per strut for overhaul. ****, that's a big difference from $125 to $200. anyhow, I was running the Tein HA coilover for about 50k miles now and they are still going with no prob. with the HKS being a monotube inverted struts, they should be more superior setup over the Teins...so it's funny how they go clunking after 10k miles or so. I was told this is very typical of HKS hypermax coilovers, and not others. if you ask me, I think they should have free overhaul for these :-)

True, so true. I think the Hipermax series are more geared toward track-use only vehicles, and aren't meant to be abused on daily-driven roads. I would gladly take time to swap them in and out between a set of stockers and use them only for track days, if it didn't mean I would need a $300 alignment job everytime.

damn! $300 for alignment job? sheesh that's expensive. I only pay bout $80 at Wheel Works.

What do you expect in a country where people pay $100+ for a pair of used Levi's jeans? Although, that $300 includes corner balancing together with the alignment.

me n my local mechanic tore apart my hipermax RS...and found oil leaking out the bottom of the strut....so we pushed down on the strut and found oil shooting out the end...so to my amusment, i have a blown strut after about 15k of use...i mean like wtf, spend a good deal on this setup and have this happen. i dont autoX or superlap with the car, jus small minor spirited driving on some twistys....then again hawaii roads are like ass...ohhwell time to overhaul em...