SUPERPRO Radius Arm Bushes with Fitting Position Front and Rear, Front Axle for TOYOTA LAND CRUISER 105 Series

Radius arm bushes are the pivots that hold a 4WD's solid front axle in place, and on a lifted vehicle they are also one of the simplest ways to put the steering right. Each radius arm bolts to the axle housing at one end and to the chassis at the other, with bushes at both. Those bushes carry the braking and acceleration loads, let the axle rise and fall, and set the angle the axle sits at. That angle is caster, and when a lift takes it away, offset radius arm bushes, often called caster correction bushes, can bring it back. Use the vehicle search to find radius arm bushes to suit your 105 Series LAND CRUISER.

What Do 105 Series LAND CRUISER Radius Arm Bushes Do?

Locating the 105 Series LAND CRUISER Axle

A coil sprung solid front axle is held fore and aft by two radius arms. The arms stop the axle being pushed back under braking or pulled forward under acceleration, and the bushes are what connect those arms to the chassis and the axle. Worn bushes let the axle shift under every one of those loads.

Allowing Articulation

As the axle moves, the radius arms swing up and down around their chassis bushes. During articulation, when one wheel rises and the other drops, the arms also twist against each other. The bushes have to allow all of that movement while staying firm in the fore and aft direction. That makes them some of the hardest working bushes on the vehicle.

Holding the 105 Series LAND CRUISER Caster Angle

Because the radius arms are bolted firmly to the axle housing, the bushes at the axle end set the angle at which the axle sits. That angle is the caster. Caster is what makes the steering self-centre after a turn and keeps the vehicle tracking straight at speed. Change the bush, and you can change the caster.

Why Does a Lift Reduce 105 Series LAND CRUISER Caster?

When a coil sprung solid axle 4WD is lifted, the chassis rises but the axle stays where it is. The radius arms, pivoting at the chassis end, swing down to reach it. As they swing, they rotate the axle housing with them, and the top of the axle tilts forward. That reduces caster.

Less caster usually shows up as light, vague steering at speed, poor return to centre after a corner, and a tendency to wander. On some vehicles it can contribute to wobble or shimmy after a bump. A modest lift can take away enough caster to be noticeable. A larger lift can take away a lot.

How Do 105 Series LAND CRUISER Caster Correction Bushes Work?

Caster correction bushes, also called caster or castor bushes, have an offset inner sleeve. Fitted at the radius arm, usually at the axle end, the offset shifts the arm's mounting point slightly. That rotates the axle housing back, restoring some of the caster the lift took away.

105 Series LAND CRUISER Standard and Offset Bushes

A standard radius arm bush has its sleeve centred and keeps the factory geometry. Offset bushes are generally available in more than one amount of offset, so the correction can be matched to the size of the lift. The amount of correction each bush provides is listed in the product details.

How Much Can Bushes Correct on Your 105 Series LAND CRUISER?

A bush can only move a pivot a few millimetres, so the caster it can restore is limited. On a modest lift, offset bushes are often enough to bring caster back into a good range. On a larger lift, the loss can be more than bushes can recover, and correction arms or relocated mounts are generally needed.

Getting the 105 Series LAND CRUISER Offset Right

The offset only works if it faces the right way. Fitted the wrong way round, an offset bush reduces caster further. This is one reason fitting should be done by a technician who knows the vehicle, and why the alignment check afterwards matters.

105 Series LAND CRUISER Front Axle and Rear Axle

Caster only matters on the steering axle, so caster correction bushes are a front axle part. Where radius arms or trailing arms are used at the rear, their bushes do the locating job without the caster role.

What About Independent Front Suspension 4WDs?

IFS 4WDs do not use radius arms at the front. Their caster is set by the upper and lower control arms, and offset or adjustable control arm bushes can do a similar job after a lift. The principle is the same: move a pivot slightly to change the wheel's angle.

What Types of 105 Series LAND CRUISER Radius Arm Bushes Are There?

Rubber

Factory radius arm bushes are usually rubber. Rubber isolates vibration and gives a quiet ride, but it deflects under braking loads, and over time it cracks, softens and squashes out. Worn rubber bushes can let caster change under braking, which is felt as instability.

Polyurethane

Polyurethane radius arm bushes are generally firmer and hold the axle more precisely. Many caster correction bushes use polyurethane, since it holds an offset position more consistently under load. The trade-off can be a little more vibration through the chassis.

Chassis End and Axle End

Radius arms have bushes at both ends, and they are often different sizes and designs. The chassis end bush lets the arm swing. The axle end bushes, often fitted as a pair or group, set and hold the axle angle. Kits may cover one end or both.

How Do You Know 105 Series LAND CRUISER Radius Arm Bushes Are Worn?

A clunk when braking, taking off or crossing dips often points to worn radius arm bushes letting the axle shift fore and aft. Shimmy or wobble through the steering wheel after a bump can also point to worn bushes allowing caster to change on the move.

Wander and vague steering at speed are common, especially if the bushes are worn and the vehicle has also been lifted.

On inspection, worn bushes are usually visible. Look for cracked, split or perished rubber, bushes squashed out of the eye or housing, or sleeves sitting off centre. Levering the radius arm against its mount can show how much movement there is.

Steering components, wheel bearings and panhard rod bushes can cause similar symptoms, so a full front end inspection is worth doing first.

105 Series LAND CRUISER Loaded and Towing Considerations

A bull bar and winch add weight right over the front axle, and every brake application pushes that weight through the radius arm bushes. Loaded 4WDs tend to wear them faster.

Towing works in two ways. The trailer's pull passes through the radius arms on every take-off. Towbar download also lifts the front, reducing the load on the steering axle and making low caster more noticeable. A vehicle that tows regularly benefits from caster comfortably within range.

What Comes With 105 Series LAND CRUISER Radius Arm Bushes?

Kits vary by vehicle. Some cover one end of the arm, others both ends of both arms, and some include panhard rod bushes as well. Offset kits may come in different amounts of correction. Sleeves, washers and lubricant may or may not be supplied. Check the product details for the positions covered, the offset and what is included.

Should You Replace the 105 Series LAND CRUISER Bushes or the Arms?

New bushes are usually the fix when the arms are straight, free of cracks and the bush housings are in good condition. Offset bushes can correct caster on a modest lift at the same time.

The arms need replacing when they are bent, cracked or heavily corroded, or when the housings have worn oval. On a large lift, correction arms may be needed regardless of bush condition, since bushes alone cannot recover enough caster.

Fitting 105 Series LAND CRUISER Radius Arm Bushes

Replacing radius arm bushes means supporting the axle and removing the arms, so it is a job for a qualified technician. The vehicle is supported on rated stands, the axle is supported, and the arms are unbolted. The old bushes are pressed out, the housings cleaned and checked, and the new bushes pressed in, with any offset facing the correct direction.

The arms are refitted and the bolts tightened at ride height, with the vehicle's weight on the suspension, and torqued to specification. A wheel alignment is required afterwards to confirm caster, camber and toe, and a road test confirms the steering feel and self-centring.

Find the Right 105 Series LAND CRUISER Radius Arm Bushes with Formula 4x4

Use the vehicle search, then confirm which end of the arms needs bushes. If the vehicle is lifted, get an alignment report so you know how much caster has been lost, and choose standard or offset bushes to match. Always check the product details for what is included.

Radius arm bushes sit in our suspension bushes range, and offset alignment bushes help correct caster after a lift.

If you are unsure what your 105 Series LAND CRUISER needs, contact the Formula 4x4 team.