Sway Bar Link for 2021 Subaru WRX STI Base

Sway bar links are the short connectors joining each end of the sway bar to the suspension on your Subaru WRX STI. It is inexpensive, it wears out on every vehicle eventually, and it is one of the few suspension repairs most people can do at home.

Catalogs list them as sway bar links, sway bar end links or stabilizer links depending on the manufacturer.

What Do Sway Bar Links Do on Your Subaru WRX STI

The sway bar resists lean by twisting, and something has to apply the force that twists it. Applying that force is the whole purpose of the link.

When one wheel rises relative to the other, the link on that side pushes or pulls the end of the bar. The bar winds up along its length and pushes back, transferring load across to the other side of the vehicle. Disconnect both links and the bar becomes a piece of steel bolted to the chassis doing nothing whatsoever.

Because the link sits between a fixed bar and a suspension component that never stops moving, it also has to pivot through its own arc constantly. That requires a joint at each end, and those joints are what eventually give up.

Any movement in a worn link is load the bar never sees, which is why a vehicle with tired links leans more than its bar rating suggests it should.

Bad Subaru WRX STI Sway Bar Link Symptoms

• A light, fast rattle from the wheel area over small sharp bumps
• Noise that is worst at parking lot speeds on broken pavement and gone on smooth road
• A knock through the steering wheel when turning at low speed
• More lean through corners, with the body slower to settle afterward
• Play you can feel by hand at either end of the link
• A torn boot at a link joint, or rubber squeezed out from between washers
• A link visibly hanging loose or bent

Sway bar link noise is worth identifying properly before ordering, because the mount bushings at the center of the bar produce a different sound. Links rattle and knock over sharp edges, while mount bushings squeak and creak, and the noise changes with the weather rather than with the road surface.

Signs of bad sway bar links show up earliest as noise rather than as a handling complaint, which is fortunate, since the noise usually arrives before the performance loss becomes obvious.

Subaru WRX STI Sway Bar Link Kits and Whether to Buy Both Sides

Links are sold individually and in pairs, and the pair is almost always the right purchase.

Both sides have covered the same distance in the same conditions, so a link that has failed on one side means the other is not far behind it. The parts cost very little each, and the labor to do the second one separately is the same as doing the first, since the vehicle has to go back in the air either way.

A sway bar link kit supplying both sides also means the bar is working against matched components rather than one new link and one tired one, which matters more than it sounds. A worn link on one side lets that end of the bar move while the fresh side holds, so the bar resists lean unevenly and the vehicle behaves differently turning left than turning right.

The exception is a link broken by impact rather than wear. If something struck it and the other side is genuinely sound with intact boots and no play, replacing one is reasonable.

On a vehicle old enough to be on original links, buy both regardless. They will be the same age, and the second one will announce itself within the year.

Driving Your Subaru WRX STI With a Broken Sway Bar Link

Worth keeping in proportion, because this comes up constantly and the honest answer sits between the two extremes you will find online.

If a link separates, the bar loses its connection on that side and stops working there. The vehicle remains driveable, the wheel stays attached, and steering and braking are unaffected. What you lose is lean resistance, so the vehicle rolls noticeably more and feels vague, particularly in an emergency lane change.

The genuine risk is what the loose end reaches, because a broken link is still bolted at one end, which means it can swing into a tire, a brake line or a CV boot. Take the loose piece off entirely rather than leaving it dangling while you sort out the repair.

Driving with a broken sway bar link for a few days at moderate speed is not dangerous in the way a broken ball joint would be. Leaving it for months is a different proposition, and on a vehicle that tows or carries weight the handling loss is more noticeable than it would be on an empty car.

How Often Subaru WRX STI Sway Bar Links Need Replacing

There is no manufacturer interval, because the answer depends on where the vehicle lives more than how far it travels.

Factory links commonly last somewhere between 60,000 and 100,000 miles. Vehicles in salt states reach that considerably sooner, because the joint boots perish and the corrosion that follows finishes the joint quickly. Rough roads and regular towing shorten that figure further still.

Once a boot splits the joint is on borrowed time regardless of mileage, so inspection matters more than any schedule. Check them whenever the vehicle is in the air for anything else, since it takes about thirty seconds per side to grab the link and feel for play.

One side failing well before the other is normal rather than unusual, because a boot splits as a single event rather than through gradual wear.

How Much It Costs to Replace Subaru WRX STI Sway Bar Links

Sway bar links are among the least expensive suspension parts on any vehicle, and the labor is short because nothing needs pressing and no alignment follows.

What makes quotes vary so much is corrosion, because the nuts sit in the worst position on the vehicle for road salt, and a seized one turns a quick job into cutting the link off. Shops price that risk in, which is why one quote can be double another for the same vehicle.

Asking how much to replace sway bar links is really asking how likely the fasteners are to cooperate, and on a vehicle from a salt state the honest answer is that nobody knows until they try.

Doing both sides at once costs very little more than doing one, since the vehicle is already in the air and both links have covered the same miles. If the mount bushings are also due, combining the jobs saves a second visit for parts that cost very little individually.

How Long It Takes to Replace Subaru WRX STI Sway Bar Links

On a vehicle where everything comes apart cleanly, both sides take under an hour with hand tools. Each link is held by one nut at each end and there is nothing else to remove.

On a vehicle where the fasteners have seized, the same job can take an afternoon. The difference is entirely down to corrosion, and there is no way to know which situation you are in until the wrench goes on.

Allowing time for the worst case is more sensible than planning for the best, particularly if the vehicle is needed the following morning.

How to Replace Subaru WRX STI Sway Bar Links Without the Stud Spinning

This is the problem that defeats more home mechanics than anything else on this job.

The link has a ball joint at each end, and when you put a wrench on the nut, the stud simply rotates with it. Nothing is seized, the joint is just free enough to spin, and the nut never comes off.

Most links have a hex recess in the end of the stud or flats machined into it for exactly this reason. Hold the stud with an Allen key or a thin wrench while turning the nut with another, and the problem disappears.

Where there is nothing to hold, the options are an air or impact gun, which often spins the nut off faster than the stud can follow, or cutting the link. Cutting is perfectly acceptable since the link is being replaced anyway, and an angle grinder or a reciprocating saw through the link body is faster than fighting it.

Penetrating fluid applied the night before helps considerably. Heat works but needs care near brake lines and rubber components.

Subaru WRX STI Sway Bar Link Torque Specs and Why They Matter

More links are ruined by overtightening than by any other installation error, and this is the step people rush.

The joint or bushing at each end needs to retain some compliance to pivot. Torque past specification and you crush a bushing flat or preload a ball joint against its socket, and the link either binds or tears itself apart within weeks.

Use the sway bar link torque spec for your Subaru WRX STI rather than tightening by feel, since these are usually far lower than people expect for a suspension fastener. On stacked bushing designs the usual guidance is to tighten until the bushings just begin to bulge slightly at the edges and stop there.

Fit new nuts where the originals are nylon insert types, because those lose their locking ability once removed.

Set link length with the vehicle on all four wheels rather than hanging, and never force a link to reach, since a preloaded bar works unevenly from side to side and loads everything holding it.

Find Sway Bar Links for Your Subaru WRX STI

If the link body is still straight, sway bar link bushings are a cheaper repair. Links are listed under sway bars and sway bar kits with replacement brackets.

Select your Subaru WRX STI to see the front sway bar links and rear sway bar links listed for it, along with link bushing kits where the design allows them to be serviced. Every Nolathane component is backed by our warranty, a fitment guarantee and 60 day returns.