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2005-2009 Outback Suspension FAQ

707K views 2K replies 272 participants last post by  stevenva 
#1 ·
The purpose of this thread is to collect info about parts and techniques used to modify the 2005-2009 Outback for the North American market. Many of the items here will also apply to other regional markets, but the info is specifically geared towards USA audiences. This is a work-in-progress. Please comment with any new information or corrections.

General Info
The 2005-2009 USA Outback has 8.4" of ground clearance (8.7" for turbo models). This is ~2.5" more than a comparable Legacy GT and ~1" more than Australian/Japanese Outbacks. Perhaps this added ground clearance allows the USA Outback to compete better with more traditional SUVs. But that added inch certainly does not improve handling capabilities for street driving especially since Subaru did not optimize the suspension geometry for this raised height.

Dampers (shocks/struts)
The factory dampers on the 2005-2009 Outbacks are tuned very conservatively to offer a plush, somewhat floaty ride. After 30,000-60,000 miles, especially on 2005-2006 models, the dampers are already wearing out and compromising ride quality. When comparing cars with brand new dampers against worn dampers, you really notice the difference in the back seat. The worn-out factory dampers don't control the oscillations properly in the rear and you can easily get that carsick feeling and compromised handling especially when hitting a bump in the middle of a corner. The front dampers don't seem to be quite so sensitive though they wear out as well. There are several options to address this issue:
  • KYB GR-2/Excel-G 2005-2009 dampers ~$210 shipped from Suspension or AJUSA Reported to be slightly stiffer than a brand new OEM spec damper
  • KYB GR-2/Excel-G 2002.5-2004 dampers ~$250 shipped from Just Suspension or AJUSA
    - while not 100% physically identical to their 2005 counterparts, both front and rear 2002.5-2004 dampers are compatible with the 2005-2009 model. The damping rates are different and presumed to be tuned to the weight distribution and spring rates of the 2002.5-2004 cars. KYB engineers have not been entirely straightforward about the differences in damping between 2004 and 2005. It is believed that rebound damping is higher on the 2005, but compression damping is higher on the 2004. This has not been confirmed via independent testing on a damper dyno. KYB has a different model number for 2000-2002 dampers in their catalog which cost more but may be compatible as well. It is unclear what the differences are.
  • Mix'n'match dampers: Front KYB 2005-2009 damper with rear KYB 2004 dampers reported to offer good results
  • Monroe SensaTrac $300 shipped from various national parts stores - perform the same as OEM
  • OEM replacements $350 at Subaru dealer
  • Legacy GT/Koni yellow cut'n'gut conversion Koni Insert Install Step-by-Step you need to find Koni inserts that are longer than the LGT/Impreza versions. Not sure if anyone has successfully done this conversion and preserved the USA outback ride height.


Springs
  • OEM 4-cylinder springs rates approx 196# front / 308# rear and are approximately 2.5" - 3" longer than Legacy GT springs depending on the model
  • H6 front springs swapped into 4-cylinder models may result in slight increase in ride height and better driving dynamics. The theory is that the extra weight of the H6 engine up front requires stiffer springs. The rear springs between both models are reported to be the same, so no advantage from swapping H6 rears into 4-cylinder models.
  • Rallitek overload rear springs RallITEK Overload Springs 2005-2009 Outback Wagon these are a great option for folks who frequently tow or have lots of passengers & cargo. They will also firm up the ride and handling for folks who carry light loads as well. Note that these are different than the 2000-2004 springs offered by Rallitek in spring rate, free-length, and top-hat seating configuration. They are not interchangeable.
  • King Springs - King Spring Automotive Aftermarket Springs l- reported to raise Australian model 1 inch which is similar to OEM USA height. Do not raise USA model, though stiffen the ride considerably.
  • Legacy GT swap? Possible but involves swapping a lot of components in addition to the springs.


Coil-overs & spring/damper kits
Coil-overs are pretty much the same as a spring and a damper although they allow height adjustability. The height adjustability allows corner-balancing to finely tune the handling characteristics such that the responsiveness of right-turns is equal to left turns. The ability to raise and lower the car several inches is a side effect and generally considered an aesthetic modification rather than a performance modification.

Anti-sway bars
After tuning a suspension with dampers and springs, swaybars allow finer tuning of the understeer/oversteer characteristics. Outbacks typically understeer from the factory and to optimize handling, a stiffer rear swaybar can be used. In many cases, swapping the front swaybar is not necessary. The thickness of the bar is not the only indicator of relative stiffness. The attachment points and swaybar material (hollow vs. solid) affect the effective stiffness. If you upgrade the swaybars, you should also upgrade the end-links and reinforce the chassis mounts as well. Legacy GT and some WRZ swaybars should work on the Outback, though modification to the bushing/mounts may be required to prevent the bar from slipping laterally. Good quality hose clamps positioned inside of the bushings will prevent the bar from slipping.

Anti-swaybar end-links and mounts

Lift spacers/Lift Kits

Alignment
  • The factory alignment settings are not optimized for handling, they are optimized for highway tire wear. For maximum street performance, try maximizing caster and negative camber. To adjust beyond factory spec, see the camber and bushing options below.
  • Some cars are particularly susceptible to a "ghostwalking" handling issue in cold weather. It is believed the increased ride height of USA models contributes to a rear suspension geometry issue where to toe-angle can go out of spec depending on how much the car is loaded down. To combat this situation you can throw 100-200 pounds of sandbags in the back of the trunk and then get an alignment to 2007+ spec. Upgrading the rear spring rate with RalliTek springs and upgraded dampers like KYB may also help limit the amount of toe change during normal driving. Some folks have stated that the Whiteline rear camber bushing helps dial in a little more rear camber and improves the handling.


Front LCA bushings
For the front-LCA there are several aftermarket options. In general, the rear-position bushing should NOT be replaced with polyurethane because the joint is designed to rotate on an axis that is perpendicular to the bushing-through-bolt. In this configuration, the OEM rubber bushing flexes while polyurethane binds. A spherical bearing is the most robust solution but has a noise/vibration/harness and maintenance penalty. The front position bushing may be safely replaced with polyurethane since it pivots on the same axis as the through-bolt and isn't designed to flex.
LCA bushing thread

Other bushings:
  • Whiteline rear upper control arm camber bushing kit adjusts rear camber up to 1.25* link
  • OEM Group "N" upper strut mounts

Camber kits/Camber bolts
  • Cusco front camber plates Cusco Front Camber Plates - Legacy BL/BP - Legacy Suspension - these rely on a single spherical bearing to both allow the strut to turn when steering and withstand the shock load of the whole strut. This class of camber plates do not last long compared to the more robust bearing in the OEM mounts or in camber plates from companies like ground control who opt for a dual bearing configuration with the spherical responsible for steering and roller-bearings responsible for shock load. The good thing is that all these camber plates are re-buildable with replacement bearings as long as you know the size of the bearing.
  • Ingalls Engineering 81260 14mm camber bolts (for front struts)
  • H&R Triple C 14mm camber bolts (for front struts)
  • SPC EZ Cam 14mm camber bolts (for front struts)
  • Whiteline rear upper control arm camber bushing kit adjust rear camber up to 1.25* link
 
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#5 ·
King Springs and AUSTRALIAN rear KYB dampers

To clarify the effect of King Springs on ride height, as per "?" in post #1, I have fitted raised King Springs to my Aus spec 2.5 litre 05 Outback, which raised the suspension ~ 1 inch.

I understand that King Springs also manufacture standard length replacement springs.

For what it is worth, raised King Springs and AUS Specification KYB rear dampers [part no. 341354, other code on box 9A29] give an excellent ride. Presumably this same combination would give a similar result on the US Spec.

It might be worth asking KYB to advise which of the US spec rear struts is the equivalent of the Australian part number / code. It may well be the US 2000-2004 dampers

(MODS: Hopefully this feedback on an actual installation is useful in this FAQ thread. If not, please delete / modify.)
 
#6 ·
Had Kings on my '09 and the ride height was exactly the same as stock.

Also, the 00-04 dampers are mechanically identical to the 05-09 dampers. The rebound damping force differs somewhat according to an unsophisticated bench test I did myself. There will be NO change in ride height if using them. The 00-04 dampers appear to have more rebound damping.
 
#1,633 ·
Sorry for bumping an old thread, but my experience with a 2006 NA showed that the 00-04 KYB rear has a smaller spring perch than that spec'd for 05-09. I was uncomfortable with the reduced surface contact of spring to perch and returned the 00-04 KYB for the 05-09 KYB. Other than the perch diameter, the mechanical dimensions were indistinguishable.
 
#7 ·
Good idea. Here's a few bits that might help -

Stock spring rates are 196 front, 308 rear. OB springs are approx 3" longer than LGT springs.

Rear spring perch KYB replacement - SM5214 (around $25 on Amazon)
Front bearing plate (AKA tophat) - Moog part # K9559 (around $60 or less, several manufacturers)

Common mistake when re-assembling the front struts - the pyramid shaped washer points up! Meaning the narrow surface should contact the bearing in the tophat.

Coilover options -

Lift Kits -
 
#305 ·
Not to muddy the discussion, but I'm curious if anyone can comment on the effects adding a 'spacer style' 1" lift 'kit', such as discussed in Post #7 of this thread, would ultimately affect the ability to get proper (or more specifically to reach the necessary Camber/Toe) settings. I'm tempted to go with the 1" lift when I do the struts (soon), but I'm concerned it may cause more issues trying to get the alignment right, thoughts?

Lift Kits -
 
#9 ·
Rear sway bar

My selection for the RSB was:
Whiteline RSB BSR39Z - 22mm - Heavy Duty adjustable - 2 link points at each end - under $200 for the part. (see pics)

Whiteline also offer the BSR39, again 22mm, H/D but single attachment point at each end.

Whiteline also offer Front sway bars and rear camber adjustment kits (+/- 1.25degrees).

Website is
Whiteline - Performance Suspension Products for Maximum Grip, Handling & Performance. Whiteline Adjustable Whiteline Sway Bars Adjustable Anti Roll Bars Anti-Roll Bars Stabiliser Bars Stabilizer Bars Anti Sway Bars Anti-Sway Bars Camber Kits Caster K

Other options are
Rallitek

Possibly also
Subaru WRX rear sway from what I've read on posts...
 

Attachments

#10 ·
My selection for the RSB was:
Whiteline RSB BSR39Z - 22mm - Heavy Duty adjustable - 2 link points at each end - under $200 for the part. (see pics)
That is alot of bar for the stock chassis mounts to deal with. It seams some spirited drivers even report problems with the chassis mounts bending with the stock bar, so you might want to consider reinforcing those mounts, either with a kit like AVO's, or some other means.. ;)
 
#12 ·
I love the idea of this, but just want to let you know that our benevolent overlords at Autoguide have limited us to only editing posts for 30 days. So after 30 days you will be unable to edit your first post. So I recommend trying to get as many changes as possible in there as soon as possible.
 
#14 ·
Sway bar options

many options, some of which are really for the Legacy, but SUPPOSEDLY fit

rear, in my perceived order of stiffness:

Stock 15mm solid noodle
JDM 20mm hollow...I've heard maybe 50% stiffer (heresay)
Swift 20mm solid (flexy for its thickness) claimed 17-23% stiffer than JDM
Cobb 22mm hollow adjustable:195%-225% (soft-stiff settings) stiffer than 15mm stock??
Rallitek 19mm solid. Somewhere in between Cobb on soft vs stiff settings
Don't know relative stiffness of the following:
AVO 20mm
Whitelines 20mm
Perrin 22mm, and 25mm
Cusco 21mm???
Progress???

All these brands have front bars, except maybe JDM:
stock 21mm solid
Swift 22mm: 23% stiffer than stock
Cobb 25mm hollow: 47% stiffer
Don't know relative stiffness of the following:
Rallitek: 22mm solid
Perrin 22 & 25mm
AVO
Whiteline 22 mm
Cusco 23mm??
Perrin 25mm

Rear mount stiffeners by:
Cobb
AVO
Perrin
Progress

Someone chime in where I'm wrong, and I'll edit

FWIW< quite some time ago OhBe1 (@legacyGT.com) reported re rear:
"FWIW, using vel0mac's dimensions:
Rear, compared to our LOBW's 15mm bar:
16mm solid USDM LGT is 29% stiffer
20mm hollow JDM is 111% stiffer
18mm solid Swift is 107% stiffer
22.4mm hollow Cobb is 263% stiffer

Front, compared to our LOBW's 21mm bar:
25.6mm hollow Cobb is 47% stiffer."

I think he is wrong on some (hollow vs solid), but I may be just as wrong as him.
Some of these may not be available any longer

*****One concern surfacing (mostly from Rallitek) is overdoing things: stiffer rear springs along with stiffer rear sway bar could equal twitchy, oversteering, behaviour, and compromised ultimate traction in the rear.*****
 
#15 ·
shocks / struts

here are the slim pickings that I am aware of:

rear:
Stock (by KYB): few fans of these
KYB 341443: 18% stiffer rebound, 9% stiffer compression: spec'd for 05-09
KYB 341276: approx stock rebound, 30+% stiffer compression: spec'd for 00-04, but talking about using on 05-09
KYB 341354 non US: 34% stiffer rebound, 46% stiff compression THAN 341443 (60% rebound/59% comp over stock???)
Monroe SensaTrac: unknown specs, but not well liked in reviews
Bilstein BTS 5056: JDM: incl springs: few have them (one guy?), expensive, supposedly the best option for daily street use

Bilstein has unobatainium desireability, KYB 341276 has several fans lately
good luck getting non-USDM KYB's in USA

Megan Racing Coilovers: mixed reviews (some are good)
BC BR Coilovers: make sure to get the longer body vs Legacy version

Or drop down to Legacy suspension and have their Bilstein, KYB, and Coilover options...and limited height / travel.

For the front:
Stock: allegedly not too bad
KYB 339098 -99 somewhat stiffer, I don't know specs
KYB 00-04: even stiffer (at least is 1 direction), different dimensions???
KYB 334374-75 non USDM: supposedly 70% in stiffness (which direction???)
Bilsteins as above (the kit includes all 4 corners: springs/shocks)
the Coilovers above

based on only Schneider's review, the unobtainium Bilstein BTS kit has the highest regard. For the rear, the KYB 341276 (designed for 00-04 but fitted to 05-09) is becoming popular favorite among more affordable options.

Megans' have fans and foes
BC Racing as limited reviews on Outbacks, but evidently a lot of fans amongst the Legacy owners.

non-USDM KYB's hard to acquire, and requie some unknown fitment bits (but probably similar to Bilstein BTS kit)

There, now you know everthing I do. I hope this helps somebody.

DISCLAIMER: I have NONE of these installed (well, I have 100% stock and I hate it)...but not for long. Talk about analysis paralysis
 
#21 ·
For the front:
Stock: allegedly not too bad
KYB 339098 -99 somewhat stiffer, I don't know specs
KYB 00-04: even stiffer (at least is 1 direction), different dimensions???
KYB 334374-75 non USDM: supposedly 70% in stiffness (which direction???)
Just to make this relatively clear: KYB's catalog (downloadable from their website) lists three sets of GR-2s that might fit a US '05-09 Outback:

KYB 334275/334276, for '00-02 Outback
KYB 334447/334448, for '03-04 Outback
KYB 339098/339099, for '05-09 Outback

I'm not sure if the '00-04 front struts will fit a '05-09, but I think somebody somewhere mentioned that they do.

I also don't have any idea of damping rates for any of these, though I've seen some second hand information and speculation in other threads.

My current research project is figuring out what struts to put in the front of my car...

Bimmer
 
#17 ·
IIRC, Cobb used to offer the only hollow front; they also had a hollow rear; but they don't offer any bars anymore. But things change, and I could be wrong even if they didn't.
The Subaru JDM hollow 20mm rear bar should still be available.
My numbers assumed all bars have the same geometry, and are made of the same iron alloy (steel), same heat treatment, etc. Relative stiffness calculated by 4th power of diameter. A bar twice as thick would have 16 times the stiffness (1500% increase!).
If anything, I think Swift uses a different alloy, so may be stiffer than the dimensions indicate.
Also recall there are front bar fitment issues between the turbo and N/A models.
 
#18 ·
Does anyone that has swapped to the LGT suspension have any alignment specs? There has been some question as to how much it throws the toe and camber off by dropping the height. What I want to know is whether it throws things off to the point that they can't be compensated for with an alignment and whether the toe will be thrown off enough to effect handling and tire wear.

It would be excellent if we could document some real world effects of using LGT struts/springs. It opens up a new world of possibilities, but I and many others are on the fence about the side effects.
 
#22 ·
The 04 KYB spec fronts do fit 05-09, MoPower used those along with the rears but mentioned they felt too damped, as in too rough, and stated that if he could do it again he'd use the 05 fronts & 04 rears. I took his advice & the results have been excellent.

I did the LGT swap back in 05, I may have been the first? The alignment numbers were acceptable - Front camber was -.3/-1, front toe was -.3 on both sides, caster was 6.5. Rear camber was -2, toe was about .8 on both.

Compared to stock ranges the front toe was about .2 out & it led to some scrubbing I think. The camber & caster numbers were well out of range but were welcome, they improved road feel quite a bit.
 
#23 ·
The 04 KYB spec fronts do fit 05-09, MoPower used those along with the rears but mentioned they felt too damped, as in too rough, and stated that if he could do it again he'd use the 05 fronts & 04 rears. I took his advice & the results have been excellent.
I don't want to hijack the FAQ thread here, but just to be clear:

You would say that the '05-09-spec KYB GR-2s for the front were an improvement over the OEM front struts?

I'm tempted to think that the more damping, the better (I can hardly imagine the Outback's ride becoming too harsh), but I do remember MoPower complaining about the ride quality with the '00-04 spec KYBs.

Bimmer
 
#25 ·
Not a hijack. The first few posts will collect, distill, and organize the info - the rest of the thread will serve as discussion.


Right before the 30 days editable expiration runs out I'll post another "placeholder" and link the first post to it so folks can traverse through the distilled info easily. Plus we can always get mods to clean up the thread after the info has been incorporated into the main posts to everyone's satisfaction.
 
#36 ·
Front strut mount bolt pattern compatability - Gen 3 & Gen 4.



Thanks for that link Boulderguy,
The application list includes the Gen 3 Outback, but not Gen 4.

Does anyone know if the front strut mounts for Gen 4 (04 - 09) is the same as for Gen 3 (Up to 2003)?

Am asking the same elsewhere, once I have an answer I will post here.
 
#33 ·
about springs

Rallitek makes rear springs allegedly 18% stiffer than stock. According to some sources, that is a BIG difference...perhaps too much. I've been looking for a more mild upgrade, and came upon people putting Baja springs in their older (2003-4) Outbacks...which raised height and increased stiffness. Now, 05-09 Outbacks already have the raised height vs the older Outbacks, and given the cross-applicability of the GR2 and Monroe shocks, I thought MAYBE MAYBE the Baja springs would fit our Outbacks....no idea how stiff, or what they would do to ride height (other than perhaps keep height the same). The Baja's coil diameter (the thickness of the actual metal) is thicker than our Outbacks. For all I know, same as Rallitek's. But the good news, is there is a front Baja spring, not just a rear.

Anyone know of someone who has done this, or a way to get better specs?
 
#35 ·
Rallitek makes rear springs allegedly 18% stiffer than stock. According to some sources, that is a BIG difference...perhaps too much.
I find it really good with the new springs... mind you nothing has snapped yet... :)
 
#38 ·
Thanks Cobber,

I have asked the question of Subtlesolutions as well. They will be able to confirm whether the lift blocks for both models have the same bolt pattern or not.

If they do it will make the Kingsprings and Subtlesolutions "2 inch" lift even better than it already is!

Have just spoken with Whiteline and the answer is NO - minor changes made by Subaru to the top strut mount mean that they won't fit the 04-09 (Gen4) Outback.
Apparently Whiteline do intend to manufacture a mount to fit the GEN4.

:28::28::28::28::28::28::28:

IMHO, these minor changes are a plot by Subaripoff to make after market parts difficult to manufacture and as expensive as possible!
 
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