Stock sway bar end link longevity

[surmiser]

I haven’t found any threads dealing with sway bar (aka anti-roll bar / ARB) end link longevity so I thought I’d share my experience.

 

My stock end links wore out on me at about 27000km (roughly 17000 miles). About 22000km (roughly 14000 miles) of that mileage was done with a Whiteline 22mm adjustable sway bar, which I’m still using. I didn’t upgrade my end links when I installed my Whiteline sway bar because the consensus here was that stock end links are good enough even for the track (and I’m not saying they aren’t; bear with me).

 

How did I know my stock ends links were worn? The classic symptom of metallic knocking sounds, especially when going over speed bumps, or going down twisty car park ramps at an angle.

 

I checked my coilovers, etc, just to be sure. Seemed okay, so I changed my end links. Serendipitously, I’d ordered aftermarket ones and they arrived a few weeks after my knocking noises started. After my stock end links were removed, I examined them. Everything was fine except the ball joints, which were obviously worn out. One side was very loose, while the other side was moderately loose. So, obvious ball joint wear on both sides, but different wear rates.

 

I don’t know how long all of your stock end links have lasted, but I expected mine to last a little longer. I’m not upset, since I was going to upgrade to aftermarket ones anyway (mainly for the benefits of PU bushings), and I’m prepared for accelerated wear and tear because of my mods and the way I drive, but I am a bit surprised. On other car models, I’ve seen worn rubber bushings and even links arms broken clean through, so I was more on the lookout for that sort of damage.

 

My experience could be atypical because 90% of my miles are from city driving, and my daily route’s littered with speed bumps galore. I’m also on coilovers with a front strut brace, in addition to my Whiteline sway bar, so I speculate (I could be wrong) that the increased spring rates, etc, might be working my end links harder. And I have aftermarket brakes, and relish braking later and harder than I need to, so that probably doesn’t help. If you mainly track your car, or drive on even roads, then your end links may last longer. Just be aware that even city driving can wear out end links. Ymmv

 

It’s just something for folks to consider in case you’re considering upgrading to a sway bar that’s 22mm or thicker. 19mm and 20mm sway bar upgrades seem to be more common here, and will likely give your end links less of a workout. Personally, I wouldn’t have done anything differently, except perhaps upgraded my end links a little earlier.

 

For those who are interested, I upgraded to SuperPro non-adjustable end links with PU bushings:

 

 

 

As you can see, the dimensions of the SuperPro end links and the stock ones are almost identical, except for the beefy PU (polyurethane) bushings:

 

 

 

And here are some general post-install pics. The ball-joint end attaches like the stock one but the PU bushing end’s a bit of a squeeze:

 

 

 

[YeuEmMaiMai]

how did they wear out. I am at over 40K on a 14 and when I replaced my swaybar at 19K the OEM ones were just fine... I tore the boot on one so I replaced both of them and the replacements are still fine after 20K on them

[surmiser]

how did they wear out. I am at over 40K on a 14 and when I replaced my swaybar at 19K the OEM ones were just fine... I tore the boot on one so I replaced both of them and the replacements are still fine after 20K on them

 

 

I don't know man [emoji51] Unless my stock units were faulty, my only conclusion is that it must be some combination of my suspension setup and my use cases. The ball joints were so worn out that one of them was floppy!

 

Thanks for sharing your end link longevity, which shows that mine's probably not typical. Is your suspension setup stock though? If it is, then maybe my coilovers, thick rear sway bar, aftermarket lower adjustable arms, etc, are the culprits for the accelerated wear.

 

Other 6th gens where I am that are running 20mm sway bars with stock suspension are still running their original end links at 20k+ miles, which reinforces my suspicion that it's all down to my stiff suspension setup.

[GTEASER]

2012 Legacy GT - currently still on original rear end links, installed 22mm Whiteline rear sway bar at 8k miles, currently 53k miles on the car, Koni shocks and H&R springs installed at 21k miles, twisty canyon road commute driven spiritedly almost daily, 2 track days, no issues.

 

2009 Forester XT - currently still on original rear end links, 2014 STi suspension and 20mm OEM rear sway bar installed at 53k miles, currently at 86k miles, twisty canyon road commute driven spiritedly almost daily, no issues. Side Note: one of my original front end links took a poop within a week after lowering the car -2.5" when the STi suspension went in. Replaced with Moog OEM replacements and no issues.

[surmiser]

2012 Legacy GT - currently still on original rear end links

...

 

2009 Forester XT - currently still on original rear end links... Side Note: one of my original front end links took a poop within a week after lowering the car -2.5" when the STi suspension went in

 

 

Thanks for the info.

 

I don’t get it then. Why did my rear end ljnks die on me so early? Could it be the endless speed bumps in my daily commutes? And I do mean endless. I try to slow down for them, but still... I see new front arms (or at least front arm bushings) in my future.

 

Re: front end links - Now I’m kinda worried about mine dying. I actually tried to pre-emptively swap them out for SuperPro ones but those my shop ordered were the wrong size. A 2.5” drop, eh? My drop’s only 1.5”.

[Fiatz79]

Thanks for the info.

 

I don’t get it then. Why did my rear end ljnks die on me so early? Could it be the endless speed bumps in my daily commutes? And I do mean endless. I try to slow down for them, but still... I see new front arms (or at least front arm bushings) in my future.

 

Re: front end links - Now I’m kinda worried about mine dying. I actually tried to pre-emptively swap them out for SuperPro ones but those my shop ordered were the wrong size. A 2.5” drop, eh? My drop’s only 1.5”.

 

Could certainly be the terrain on your commute.

It could ALSO be that you have a heavily modified suspension.

(Note: I replaced my RSB).

I suppose if you re-engineer there may be consequences.

(Longevity being at the top of the list).

[gathermewool]

Twisty roads won't kill endlinks. Potholes and excessively rough roads kill endlinks.

[surmiser]

I suppose if you re-engineer there may be consequences.

(Longevity being at the top of the list).

 

Absolutely, which is why I've been prepared for stuff wearing out. Just seemed a tad premature, all things considered, which is why I'm curious if anyone else has run into worn-out ball joints on 6th gens. Sounds like it's just me at this point. I'd better keep an eye on my front end links.

 

Twisty roads won't kill endlinks. Potholes and excessively rough roads kill endlinks.

 

Yeah, which is why I figure it's the speed bumps and the steadily decreasing quality of the roads where I am, thanks to constant construction, and cost cuts that stop them steamrolling over patched bits to even them out. Some days I almost (almost, but not quite) regret not getting an Outback cuz it feels like I'm offroad on certain ridiculously uneven stretches.

[GTEASER]

Are the speed bumps all the way across the lane perpendicularly? If both wheels are going over the bump at the same time the sway bar is just spinning freely in the mounts and very little pressure is put on the end links because they are both moving up and down at the same time. Now if one wheel goes over a (speed)bump and the other doesn't, that twists the sway bar and puts pressure on the end links.

[surmiser]

Are the speed bumps all the way across the lane perpendicularly? If both wheels are going over the bump at the same time the sway bar is just spinning freely in the mounts and very little pressure is put on the end links because they are both moving up and down at the same time. Now if one wheel goes over a (speed)bump and the other doesn't, that twists the sway bar and puts pressure on the end links.

 

I understand what you mean. And that's exactly my problem. My daily commute has these crazy tight spaces where I've got not choice but to let one wheel go over humps before the other side. And because they like to build speed bumps high over here, I sometimes have no choice but to approach from an angle in order to avoid scraping my front lip, which of course again means one wheel going over the bump before the other. At least 10 big bumps a day, every day; sometimes way more than that. Let's see how long my SuperPro end links last. At the rate I'm going, I suspect I'll have the dubious honor of trying a whole bunch of aftermarket end links on for size.

[XT-sub]

... My daily commute has these crazy tight spaces where I've got not choice but to let one wheel go over humps before the other side. And because they like to build speed bumps high over here, I sometimes have no choice but to approach from an angle in order to avoid scraping my front lip, which of course again means one wheel going over the bump before the other. At least 10 big bumps a day, every day; sometimes way more than that. ...

 

My guess is; that is the problem along with the 22mm rear bar & the Whiteline rear swaybar support braces. You get a lot of different wheel articulation going over the speed humps at an angle, therefore the stiffer swaybar & swaybar components put more stress on all the rubber bushes & end link ball joints (the Whiteline rear bar support braces should stop the swaybar bushing brackets from flexing so they should be ok).

 

When I was carrying out tests on my current Liberty (Legacy) with the 16mm stock bar & the 19mm STi bar, I mounted an action cam under the rear to video record the difference between the two under various driving conditions. Surprisingly even though the bar & the bushes were moving constantly on a rough road & even on a smooth street surface, the largest movement by far with both bars & bushes (& therefore stress on the end link components, brackets & bushes) was when I was backing out & driving into my driveway very slowly at an angle over the driveway approach. Even cornering very hard through a tight corner wasn’t anywhere near the amount of movement, I was surprised at how little movement cornering caused.

 

The street to driveway junction at the gutter in our street has a fair difference in height, much like the change in height of a speed hump, so this would be very similar to driving over speed humps at a slight angle (i.e. one wheel before the other).

 

With your previous setup (22mm bar & original end links) were the end links vertical or were they at a slight angle when looking from the rear? The 19mm STi bar that I tried was a bit shorter than the 16mm bar so the end links were at a slight angle with the 19mm bar. By looking at the video I could see the end link was being pulled at an angle when entering & leaving my driveway, but whether this was putting more stress on the end link ball joint & rubber bush I don’t know. Of course if the end link angle was great enough it could cause the ball joint to run out of movement & eventually fail. Hopefully the polly bushes in your new end links will stand up better than the rubber ones.

 

BTW – you did the right thing with the swaybar support braces with that bar (I asked Whiteline at the factory here in Australia quite a few years ago about when are the support braces required & they told me when you go to a 22mm rear bar or larger – they are not required on a 20mm or less).

 

I like your setup for rear camber adjustment.

[surmiser]

...the largest movement by far with both bars & bushes (& therefore stress on the end link components, brackets & bushes) was when I was backing out & driving into my driveway very slowly at an angle over the driveway approach.

 

I never did that (action cam monitoring), so thanks for sharing your findings, because this makes me conclude that all my sedate grocery runs, and driving family to work and school (which is the bulk of my commute), probably put my end links under more strain that I'd have guessed, thanks to always having to angle over humps and driveways.

 

With your previous setup (22mm bar & original end links) were the end links vertical or were they at a slight angle when looking from the rear?

 

When I first installed the 22mm bar with the stock end links, I was at stock height and the 21mm (softest) setting. End links were more or less vertical then. After dropping my car 1.5" on coilovers, the end links bent at a sharp angle, so I shifted to the 22mm (medium) setting, which put the end links vertical again. So there shouldn't have been extra stress from odd end link angles.

 

BTW – you did the right thing with the swaybar support braces with that bar

 

Well, they came with the bar, so I didn't see any reason not to put them on. As a bonus, they look quite cool

 

I like your setup for rear camber adjustment.

 

Thanks but it's not like I had much choice, because dropping my car 1.5" produced 2 degrees of negative camber, which looked good but made for uneven tire wear.