Stock rear shocks / struts gone at only 40,000 miles?
 

I now have 40,000 miles on my FR-S, as it is my daily driver year round. The rear suspension is again acting up, this time under hard acceleration out of corners. I thought something was broken, like a sway bar end link, but looking under the car I can see nothing amiss with the structural parts such as bushings, links and control arms. The right rear shock is leaking very badly, the left rear is better, but is still leaking significantly. It appears that both are in need of replacement.

I liked the handling of my car before, so should I go with the stock shocks again (for another 40,000 miles:thumbdown:) or go to something like Bilstein HD shocks. I am on a very limited budget, so coilovers are out of my price range (maybe I'll win the Ohlins lottery). Since this is a daily driver that does see Minnesota winter use, I would prefer to stay with the stock height and don't feel a need to change the springs. I don't think the front shocks need replacement at this time, but I will have to check. If the fronts are good, the stock rear shocks would be a good match, but would Bilstein HD's change the setup enough to ruin the handling? What solution would you recommend, and are there any other things you would check on the suspension that I may have missed?

I have been an instructor for my local BMWCCA Chapter for over 15 years. I don't currently earn a lot of money, so I mostly stick with a shorter local track when I do get out. This track is slightly faster than an autocross course, usually 3rd or 4th gear depending on the tires, track condition and type of school I am instructing for. Speed is usually rule-limited to 55 mph. I do occasionally get to a longer local track that allows higher speeds. When I got my FR-S, the suspension had too much motion for my driving style. The front end was imprecise, especially under hard braking at turn-in. The rear of the car was bouncing all over the place in various different maneuvers. I fixed all of the problems with some relatively inexpensive braces and bushings. Here is the list of my modified suspension parts:

Password:JDM Ultimate Lateral Brace (strut tower brace)
Carbing Front Crossmember Brace
Perrin Front Control Arm Brace
Perrin Positive Steering Response System - Offset Bushing
SPC Camber Bolt Kit Front
Whiteline Positive Traction Kit (rear subframe bushings)

Tires:
• Michelin Primacy HC 215/45R17 on stock wheels (probably replaced with Michelin Pilot Super Sport next year)
• BF Goodrich g-Force Rival 225/45R17 on Enkei RPF1's
• Winter tires (Bridgestone WS80 205/55R16 this year)

ONLY 40,000 miles?


that's kind of the range of when one should replace their shocks/dampers in most normal cars

Mine did the same after only 15000 km ( 9000 miles).
A bit disappointed they leak so early but good excuse to by some better one's.
Problem find better one's not so expensive and keep oem spirit.
I love how the car handle with Oem suspension and oem michelin primacy tyre, drifting every where with out going crazy speed with lot of feed back and at speed that i will not end up in jail.
If I want to end up in jail or do track time I take my tuned Audi RS2 with semi slick.
At least for me it's why I bought the GT86 I knew it was a fun SLOW car.
Even my Van is faster on straight and may be also on a mountain road but no where as FUN.

I believe most shock manufacturers suggest replacement at 50k miles (80k km's), although a leak would typically mean something is much more worn than expected at this point.

Lol a VAN that's faster on straight and mountain roads? What the heck kind of van do you drive?

It's a VW T5 long wheel base 4motion with VW R32 engine with 260/264 cam's and vortech supercharger, AWIC running on E85 about 370 whp. it got H&R sway bar, KW V3 coilover, 19' OZ ultraleggera and Bridgestone RE 050 255/40/19. remove all heavy part so it's 1900Kg (4188 pound) empty.

My dream Van:

[ame="http://www.youtube.com/watch?v=St1l6QZZTnI"]800PS VW BUS TH2RS UND 2010 PORSCHE 911 TURBO - YouTube[/ame]
saw one second hand for sale at 100000€ last year

That one must more close to mine on performance
[ame="http://www.youtube.com/watch?v=kB37QIZfgEI"]MTM T500 VW Transporter [GTspirit.com Overview] - YouTube[/ame]

koni shocks?

These would be a nice option if they were available. It appears that only Koni Yellow shocks are available for the FR-S, and it appears that these are not designed to work with the stock springs:

According to the information from FT86Speedfactory:

KONI Yellow shocks offer the same exceptional road-holding as the sport shocks, but are especially designed for cars that are fitted with lowering springs which are shorter than the original springs.

The HDs sounds like a great option for what you're trying to accomplish. I wouldn't go OEM again after hearing that story.
I've had Bilsteins leak on me, but they always rebuild them for free. You won't get that with OEM.

how about get Ebach Pro Kit Spring +Koni?
Pro kit only drops 1 inch

This would probably work great, but I am trying to keep the cost down to just shocks.

That is equally hilarious and awesome! :bow:

you don't hang around the autocross scene much, do you....




a koni yellow is a perfectly good replacement for the OEM unit. You will not experience any adverse effects.

It has a slightly better compression characteristics and somewhat adjustable rebound characteristics. If you're only driving on the street you can put them on full soft and enjoy life.