I have read through all of the suspension FAQ over the last couple of years several times kind of wondering when I would need to replace anything. Well I think the time has come. I have 201,000 on my OEM suspension and things are finally not feeling so perfect anymore I think I got my money's worth.

I just want to make sure I didn't miss any options because the OEM replacments seem a bit steep on price.

Before getting into that though, I did do a little "forced" upgrade in the last year. In the last two years I already had lower front ball joints go out and fooled around with cheap lower compression rods from Autozone and OReilly and finally took them all back for full credit and went "all out" for me at the time . Don't waste your money they are all junk! One of them only lasted 6,000 miles! So I then bought brand new OEM arms, pushed the bushing out and put in SPL spherical compression rod bushings. So, while I was under there I put in both sets of Whiteline bushings in the front lower translink arms too. One of the OEM bushings was starting to crack a little so it was time for that too even though I experienced no signs of the arm actually moving yet like the pictures here show when they fail. And I have solid diff bushings. Other than that it is all bone stock.

Shocks are starting to rattle and I have the rear end clunk from the bottom shock mount when going over small sharp bumps are my complaints.

And stock is what I want to replace it all with! No ride height change. So my #1 question is are there ANY options other than the OEM replacments I want to consider to retain stock ride height? I have not seen anything yet that is not a drop in ride height.

Last time I priced front/rear shock/springs plus all of the new mounting hardware I was up over $2,000 at Courtesy ( didn't even check shipping - might be better off at local dealer overall).

I would really appreciate any last advice on other hardware I might forget at this mileage so I can get a list together and prices. I'm figuring that the front end is decent now except for shock/spring but the rear is probably due for some bushings. Which ones are probably necessary? I've already tried to price every mounting part for the shocks from the exploded views but what are any pieces that people tend to forget about and foolishly just replace the shock and spring only and find out that all of the moutning hardware was worn out?

 

Springs need many more years to wear out. Just get some new shocks (Koni or D-Spec ) and you are set. Then you should also look not sway bar bushings, maybe endlinks and shock mount bushings.

 

Really?! That's good news for me. That would cut the price nearly in half from what I remember. After all these years though I was under the impression that not replacing springs was one of people's #1 overlook when replacing a worn out suspension and would not be a complete job unless you replace your fatiqued springs. In fact I thought I remembered extreme cases where replacing one without the other would quickly wear out the new item becuase the pieces you did not replace allowed the new piece to wear out - maybe those cases were just spring/shock mismatches though.

So, since I just noticed some rattling again after being quiet for a year I am ASSUMING that the shocks are finally bouncing because it is a different rattle then when the ball joints went out and need to check them. I am going to quickly act on this because my biggest fear is that the shocks could cause the new compression arms I just paid for to wear out again? If the shocks are worn badly can that blow out another perfectly good lower ball joint?? I've owned a couple of other high mileage cars and there becomes a point where ignoring one thing for awhile causes more things to wear that didn't need to and a chain reaction occurs leaving you further behind in cost overall.

I'm just thinking out loud though and will DEIFINATELY be looking into this and appreciate the simple advice.

There must be a way to double check them and make sure they are still usable after 200,000 miles. I'm sure I can research that on my own. Keep the comments coming if you have any other advice everybody...

 

There are race shops than can check your springs. Depending on the year of your car I would just grab a set of used springs with the updated rates.

 

Used stock suspension parts would be good. Congrats on hitting 200k on your z. Hopefully a couple years from now we'll here you hit 300k or 400k with no major problems.

 

There are a couple of speed shops over my way with the drag strip in the area but not sure if they have a garage bay or just sell stuff. I think a coulpe of guys at work could get me some help with this now that you mention this route.
I've got an 05 base, so I know that at least I am better off than an 03 with the porpoising problems, etc. I think I would stay with 05 if they are not fatiqued
thanks for helping me decide which direction to head off in

 

What's wrong with the 03? This old guy in my neighborhood had 270k miles on his 03 with minimal issues.

 

I was considering this for the last few days but am honestly scared. When you read up on how long a shock, or a clutch, or tires should last it all depends on how the person drove the car. I could look and find shocks with "only" 40k on them and they may be ruined.
As my car gets older I do consider these things but I just don't know about doing this for shocks.
I DO want my car to go 300-400k so in that sense I almost have to get new so it lasts for sure. The used route would only be to save money and when the OEM lasted this long, hopefully brand new of OEM or aftermarket will give the same results and be the only one set of shocks I have to buy for this car then. I've got the money I just don't want to spend it foolishly and also it becomes harder to spend top dollar as a car gets older and older. I only looked at used for one day so I may still consider it.

 

Nothing at all!
Since I never mentioned I had 05 I was assuming terrasmak's comment about rates may have been the difference between 03 and 05. From what I read, many 03 owners were disappointed by the ride quality early on and what they described as bouncing on the highway.


Off topic now, but I started this 270k?! Wow. Is his engine still running strong? I'm curious at what point does the VQ wear out if well maintained. I'm picturing someday I'll just loose power gradually and compression will be down and the top end will need to be rebuilt to continue on past 250, 300, 400k (however long it lasts)? I still have never run across a "worn out engine" thread. I've owned old cars that were 20 years old but never had over 100,000 miles on them.
I only use about 1.5 quarts per 3,000 miles. 2/3 of my driving is 80mph highway cruising and it takes 40 miles to get to work. So many of my contaminents burn off probably, showing a more true oil use than someone who never leaves town. And I'm sure that the valve covers are still leaking (they were at 100,000 plug change) so I'm sure a lot of that is just lost out the valve cover.

 

The guy drove his z everywhere since he bought it brand new in 03. He told me stories how he drove cross country multiple times, driven through canada, mexico, had it exported to Germany and driven it on the nordchelife course, on the 24 hour course and even Prague where they shot the run commercial for the z in 2002. It's really cool seeing all the pictures he has taken with his z at these places.

I've driven his z and compared to mine I notice it doesn't respond as quickly and I noticed it runs out of grunt around the 4k rpm range compared to my 03 with 27k miles. But then again my car has a lot of nismo parts on it.

 

I would not replace your worn OEM parts with new OEM, it's not worth the cost of buying new OEM vs cheaper quality aftermarket

You could very easily just replace your shocks with a set of Tokico HP's without breaking the bank and everything else I would just source from someone on the forum.

 

best stock options:

Koni yellows or Tokico D-specs
Revised springs
New Bushings

Your done.

If you ever want adustability, get the koni yellows, because you add adjustable apring perches to them for less than 100 a shock and have them revalved if you ever want to move your suspension grade up.

 

05 base, you already have the updated springs. Just grab the shocks (Koni or D-Spec) , probably some shock mounts and you are good since your bushings are already swapped.

I will mention sway bar bushing again, they are cheap and the OEM one is soft as hell when new. Best to just get a set of Hotchkis bars, that will really make your car feel updated with the other parts.

 

Thanks for the confirmation about spring revision. That was my next research topic to see if I missed something. I knew there were a couple of revisions but unless they made one more for HR models (06-09) I thought I missed something. Rather than be worried about which revision I have I would be more worried if the aftermarket shock needed to be matched to what year spring I have. I was going to visit courtesy to see if they still sell specific year springs then how many different shock revisions there might be. I'm not to be worried about shock model vs. spring revision if I go something simple like Koni or Tockico right?

I've spent a couple of hours learning about spring design. It seems the consensus is that springs don't wear out, they can break or take a pretty big set over 20 years. The spring checker at a race shop you would have to take the springs off the car and it only verifies spring rate - nothing I want to deal with on a daily driver during the busiest season at work. I still need to decide if it still has the correct ride height. One race spring manufacturer recommends no more than about a 1% change over the life of the spring and they gurantee theirs will not change more than 2%. This is really the only other scientific way of checking a spring - measure ride height.

I find it hard to believe that with manufacturing tolerances involved in body panels and suspension assemblies that the FSM lists an exact number from ground to inside the fender lips. Front is 26.81" and rear is 27.56" (for base with 17" wheels). This is with full fluids and full tank of gas.

Well, I have 1/8 tank and measured
FL 26-3/16"
FR 26-1/4"
RL 27-1/4"
RR 27"
I bet that I could take 15 gallons next fill up and its about 6lb/gal. So 90 pounds in the rear. I took two bags of fertilizer and put them in the trunk (72lb)
front stayed the same, rear squatted down
RL 27-1/8"
RR 26-7/8"
After removing the weight the car went back exactly to my previous measurement.
Front tolerance minimum with say 2% allowed set would be 26.27"
Rear with 2% is 27.0088"
I think I'm just fine and will move ahead with the advice to get shocks only.

I KNOW that I am probably going crazy here and overthinking this but I do feel like I should be checking for anything obvious. Just want someone to say that I am and move on. Any reason to doubt re-using my springs??


So then, my last bit of debate is noticing that every alignment sheet I have in my files shows a pretty big out of spec reading on the rear toe. I'm considering doing a toe bolt lockout and get the more robust adjustable suspension arms so my alignment stays solid. And of course like some of you keep saying inspect all my rubber bushings in the rear and also consider sway bar bushings and possibly endlinks. New shock mounts,etc.
Do daily driven cars typically show signs of the eccentric bolt slipping or only with heavy track use? What makes it slip? Hard shifting, hard cornering, wheel hop, all of those things?

If I could make a final couple of decisions it seems like the hardest part will be finding some of these brands of shocks in stock. I think it was Koni that was out most places right now. I live 10 minutes from a Tire Rack so I was already shopping there last night and noticed this.

Long winded, but my last couple of questions!

 

Just reuse them , you are way over thinking. Only thing I would do is swap the rears from side to side do to 8 years on torque. The shocks, the two mentioned will be just fine, if you want to go nuts , you can also call Bilstien and find out what springs theirs are built for.

 

Just upgraded to Ohlins. I am ready to sell my Koni Yellows, if your interested shoot me a PM and I'll text you some pics. 1 1/2 years old and 10,000 miles. $550

 

Lot of overthought, just follow what was said above, you will be ok.

Your springs will never go out, you can use them for the life of the car, same thing with your toe bolts unless you snap one. Alignment will always fall out of spec, thats why you have to get it realigned every once in a while.

 

Thanks for all of the valuable help. I'm comparing shocks right now. Acutally what I meant to express earlier was that I would be concerned about how any aftermarket shock length would match up with OEM length and my OEM spring height I am keeping. NOT the spring rate like I said. I started looking at Tokico HP but that may be a little too questionable on going cheap. I'll look at the other ones you recommended. Am I going to run into length problems if all aftermarket shocks are probably built to be run not at the stock height???

 

Is there any good way to diagnose worn shocks?

The internet/mechanics outdated "bounce" test is total BS especially on a sports car that still after 200,000 miles does not easily compress by hand to even start half a bounce. Also, last time I checked (6months ago?) no leaks - but that doesn't always happen.

My mechanic took 3 stabs at determining that my front ball joint was shot and said everything looked great 2 years ago. I found it finally when torquing my lug nuts a 2nd time with the car on the ground. And I had a helper try to help me at least 6 times before that looking for the loose part to cause the rattle. The whole knuckle would move when I would torque the bolt. So I don't think a mechanic can just look at your car and say "yep, get new shocks"

Ready to pull the trigger on shocks because the car is starting to rattle on bumps and I cannot find any other supsension arms with anything obviously worn. All rubber bushings are still centered and don't look cracked from what I can see. And also the car reacts a little unpredicatble with sharp inputs into a corner. It still holds really well if I am smooth and it takes a set into the corner but I'd bet in an autocross situation I would feel like I need a new car with all of the quick direction changes. Any last advice here???
Basically, not much else could make it feel like this, right?

Also slight pulsation on braking that I am 99% sure is not the rotors. Never had a brake problem on this car to date.

I guess I am starting to answer my own question here like I tend to do but want another opinion

 

Lol we already told you man, just replace your shocks, shock mounts, and bushings and ur good. your way overthinking it, I could see if you were setting up a track suspension, there is way more thought into that process than you think, but you are just replacing OEM parts.

You have updated springs, all you need is Koni yellows or D-specs, new shock mounts, and energy suspension or some better polyurethane bushings, and your car will handle like new