Vibration in front suspension…

[Damomiddap]

Heya everyone

have a vibration in front end on freeway at speed…. Started out a little on under hard braking bug now just running straight at cruise too.

moved wheels around with no difference so not balancing issue.Leaning towards a bush rather than strut failure, is there a “know suspect” with these symptoms?

tar

 

[iggorsky]

Probably... But mine would usually disappear after about 10 minutes of motorway cruising. Annoyed me a little but not to the point to start investigation. Then at some point I changed tyres (from OEM Dunlop Sport Max to GoodYear Eagle F1 Asymmetric 5) and the issue was gone, but appeared a little later with less intensity that time. That was weird!
Then I had wheel alignment done and it has never returned since then.

 

[Damomiddap]

Yeah interesting there. Have a culprit. Lower control arm bushes stuffed. Upgraded to STI arms. Have whiteline offset ones to install along with strut tops now issue had been found.

 

[iggorsky]

Sounds cool!

 

[robo498]

So a 2017 wrx sti control arms fit or car with no issues?

 

[Damomiddap]

Well mine didn’t have the alloy arms from factory and I previously believed all levorgs had them.

yes a couple of little differences if changing from steel to alloy.

what does yours have ?

 

[robo498]

Steel.....

 

[Damomiddap]

Steel.....

Okay cool.

yeah post a pic of your brackets at the rear control arm bush as these may be different to what’s needed, although I suspect that’s only an issue on platforms like the forester and out backs.

On the steel arms, the steel spacer in rear bush is shorter and as such built into the locating stud attached to the chassis. A nut is used to secure the arm here

Easy fix. Stud is removed and replaced with bolts that are used from factory with the alloy arms.

Forward bush remains the same.

Balljoint tapper for interference fit is built into the steel arm however, not on the alloy….. they use an “adapter” cone/sleeve over the threaded part of the balljoint to create this.

soooooo if you were to source 2nd hand arms, I suspect you would only need the bolts and balljoint cones. Available 2nd hand from a wreckers or new from Subaru parts/service.

Having said all that, arms are available new and arrive complete with balljoints and bushs installed. So then only need the bolts.

The alloy arms big rear “heim joint”bush is buttery and smooth compared to rubber of steel ones. The rubber ones are a subaru fail and will eventually let you down.

I used 2nd hand ones and the fitted them up in less than 2 hours. Worth the effort. Lighter, stronger and superior bushs.

 

[Damomiddap]

Some helpful videos….

Tips and write down a list of tourque numbers

part numbers and some stuff to avoid …

 

[Damomiddap]

Oh alloy arms with balljoints and bushs still in were $250 pair. Ask for the bolts as well. I didn’t and sourced them, the balljoint cones and brackets for $50. Only used the bolts.

search gumtree for a wrecker

superpro arms available from Supercheap brand new about $850.