Suspension Arms with Fitting Position Front Axle, Rear Axle for SUBARU FORESTER SJ

4WD suspension arms locate the wheels and axles, setting where they sit and how they move as the suspension travels. Upper and lower control arms do this on independent front suspension 4WDs, while radius arms, trailing arms and torque arms locate live axles. When a 4WD is lifted, these arms work at different angles, which can push ball joints toward their limits and move camber, caster and axle position out of range. Replacement and upgraded arms are designed to restore that geometry at the new ride height. Use the vehicle search to find suspension arms to suit your SJ FORESTER.

Do You Need New Suspension Arms After a SJ FORESTER Lift?

Often, yes, depending on the vehicle and the lift height. A lift extends the suspension, so the arms sit at a steeper angle than they were designed for. On an independent front suspension 4WD, the upper control arm angle changes noticeably, which affects camber, caster and the range of movement of the upper ball joint. On live axle 4WDs, the radius arms or trailing arms rotate the axle as the vehicle is raised, reducing caster and changing pinion angle.

On a mild lift, the factory arms and alignment adjustments may still bring the geometry within specification. As the lift increases, the adjustments run out, and the ball joints can run close to the limit of their travel, particularly at full droop. That is when replacement arms are commonly fitted. A wheel alignment check after the lift shows whether the geometry can be set correctly with the existing arms or whether new arms are needed.

Which Suspension Arms Suit a Lifted SJ FORESTER?

The right arm depends on the vehicle's suspension design and what needs correcting.

SJ FORESTER Upper Control Arms for IFS

On independent front suspension 4WDs, the upper control arm connects the top of the steering knuckle to the chassis through a ball joint. After a lift, the arm angles down more steeply, which reduces caster, changes camber and can push the ball joint toward its limit. Replacement upper control arms reposition the ball joint, typically further forward or outward, to restore caster and camber at the lifted ride height. Many also allow more ball joint angle, so the joint is not pushed to its limit when the suspension droops.

SJ FORESTER Radius Arms for Coil-Sprung Live Axles

Radius arms locate a coil-sprung live front axle, running from the axle back to the chassis. Their angle sets the axle's position and caster. When the vehicle is lifted, the arms angle down and rotate the axle, reducing caster. Correction radius arms use a revised geometry or adjustable mounting to rotate the axle back and restore caster. They are typically designed for a particular lift range.

SJ FORESTER Adjustable Trailing Arms

Trailing arms locate coil-sprung live rear axles, often as upper and lower pairs. After a lift, they can change the axle's position and pinion angle, which affects the driveline. Adjustable trailing arms allow the arm length to be changed, so the axle can be positioned correctly and the pinion angle set to suit the tailshaft.

SJ FORESTER Torque Arms for Leaf-Sprung Axles

On leaf-sprung axles, heavy acceleration and braking can twist the axle and wind up the springs, an effect known as axle wrap. Torque arms are designed to help control that twisting by linking the axle to the chassis. Whether a torque arm suits a vehicle depends on its setup and how it is driven.

Fixed Offset or Adjustable SJ FORESTER Upper Control Arms?

Fixed offset upper control arms build a set amount of correction into the arm. The ball joint position is fixed at an offset that restores caster and camber for a particular lift range. They are generally straightforward to fit and set up, and they suit vehicles where the lift height matches the arm's design.

Adjustable upper control arms let the ball joint position or arm length be changed, allowing the alignment to be fine-tuned to the vehicle's exact ride height. They suit vehicles where the lift height may change, where accessories alter how the vehicle sits, or where precise adjustment is wanted. The choice depends on your lift height, how much correction is needed and whether you want the flexibility of adjustment.

Can New Control Arms Fix SJ FORESTER Tyre Wear After a Lift?

They can help when the wear comes from camber or caster that cannot be adjusted back within specification. Camber outside its range wears one edge of the tyre faster, while incorrect caster affects stability and steering return. Replacement arms that restore the geometry let the alignment be set correctly, which can reduce that wear.

Uneven tyre wear has other causes too. Worn ball joints, bushes and steering components let alignment change as the vehicle moves, while incorrect toe, tyre pressures, overloading and driving style all contribute. Have the suspension, steering and alignment checked together to find the cause before replacing arms.

Does Your SJ FORESTER Need a Geometry Correction Kit?

On some lifted independent front suspension 4WDs, correcting the upper control arm alone is not enough. A lift can also increase bump steer, where the wheels steer slightly by themselves as the suspension moves, because the tie rod and control arm angles no longer match. Geometry correction kits combine parts designed to correct camber and caster with parts that address bump steer, so several problems are handled together.

Whether a kit is needed depends on the vehicle, the lift height and how the vehicle drives after the lift. A vehicle that darts over bumps or still cannot be aligned within specification after an upper control arm change may benefit from a more complete correction.

How Do You Service SJ FORESTER Aftermarket Control Arms?

Aftermarket control arms have wear parts, just like factory arms. Ball joints, bushes and boots wear over time, particularly on a 4WD driven off-road or on corrugated roads. On many aftermarket arms, these parts can be replaced individually, using replacement ball joints, bush kits and boot kits designed for that specific arm.

Check the arms at each service. Look for torn ball joint boots, which let dirt and water into the joint, cracked or squeezed-out bushes, and play at the ball joint when the wheel is rocked. Where an arm has a greaseable ball joint, grease it at the recommended intervals. Replacing a worn ball joint or boot early is simpler and lower in cost than replacing the complete arm, so make sure any replacement part is matched to your arm.

Why Ball Joint Angle Matters After a SJ FORESTER Lift

Ball joints are designed to work within a set range of angles. On a lifted independent front suspension 4WD, the upper ball joint often works at a steeper angle than standard, and at full droop it can reach the end of its range. When that happens, the joint can bind, wear rapidly or, in severe cases, be damaged. Upper control arms with more ball joint angle, or a revised ball joint position, help keep the joint within its range at the lifted ride height. This is also why droop and bump stop settings matter on a lifted vehicle.

Fitting SJ FORESTER Suspension Arms: An Overview

Suspension arms are safety-critical and should be fitted by a qualified suspension technician. The vehicle is supported on rated stands, the arm is disconnected from the knuckle or axle and the chassis, and the new arm is fitted. Brake lines and ABS wiring should be checked for clearance and slack through full suspension travel and steering lock.

Arm pivot bolts that pass through bushes should generally be tightened with the vehicle at normal ride height, so the bushes are not preloaded, and all fasteners must be tightened to the manufacturer's torque specifications. A wheel alignment is required after fitting any suspension arm.

Get the Right SJ FORESTER Suspension Arms with Formula 4x4

Rebuilding instead of replacing? Suspension arm service kits restore worn joints and bushes on arms that are still straight. It all sits within our suspension parts range.

Start with a wheel alignment check after your lift to see which angles are out of range, and note your lift height and suspension type. Decide whether you need fixed offset or adjustable arms, and whether bump steer also needs correcting. Search by your SJ FORESTER to find 4WD suspension arms to suit it. If you are unsure what your SJ FORESTER needs, contact the Formula 4x4 team.