Universal Alignment Shims

Nolathane wheel alignment shims give workshops and home mechanics a precise way to correct camber and caster (castor) on front suspensions that use shims at the control arm mounting point. When geometry drifts outside specification through wear, component replacement or chassis settling, the right shim stack brings the wheels back into line so the vehicle tracks straight, steers predictably and wears its tyres evenly.

Each listing shows the shim thickness, pack quantity and fitment for your application, so you can build up the exact correction your wheel alignment (tracking) readings call for, whether that is one small adjustment or a series of fine steps.

How Alignment Shims Adjust Camber and Caster

On shim-adjustable front suspensions, the control arm (wishbone) pivot shaft bolts to a chassis bracket, and alignment shims sit between the two. Changing the thickness of the shim stack moves the arm?s pivot relative to the chassis, which changes the angle of the wheel. Because the pivot shaft is held by a front and a rear bolt, shims can be used to change the whole arm position or to tilt it, giving control over two separate angles from one mounting point.

Camber Correction

Camber is the inward or outward tilt of the tyre when viewed from the front. Adding or removing the same thickness of shim at both the front and rear bolts moves the whole arm in or out, shifting camber without significantly changing caster. Whether adding shims increases or reduces camber depends on whether the pivot shaft sits inside or outside the chassis bracket, so always follow the factory procedure for the vehicle.

Caster (Castor) Correction

Caster is the forward or rearward tilt of the steering axis when viewed from the side. Moving shim thickness from the front bolt to the rear bolt, or the other way around, rotates the arm and moves the top of the steering axis forward or back. More positive caster generally improves straight-line stability and steering return-to-centre, while too little can make the steering feel light and vague at highway speed.

Signs Your Suspension Needs Shim Correction

Out-of-specification geometry rarely announces itself all at once. The most common warning signs are:

• A pull to one side on a flat, straight road, often caused by uneven caster or camber from side to side.
• Wear on the inner or outer shoulder of the front tyres, a typical result of excessive negative or positive camber.
• Steering that does not return to centre cleanly after a turn, or feels nervous and wandering on the highway.
• An alignment printout showing camber or caster outside the factory range after new bushes, control arms or other suspension parts have been fitted.

If any of these appear, have the wheel alignment measured first. The readings tell you how much correction is needed, which side needs it and whether shims are the right tool for the job.

Benefits for Handling and Tyre Life

Correct camber keeps the tyre?s contact patch flat on the road, which improves grip under braking and cornering and spreads wear evenly across the tread. Balanced caster from side to side removes pulls and helps the steering self-centre, reducing driver fatigue on long trips. Together, these corrections extend tyre life, and because tyres are one of the largest running costs of any vehicle, an accurate shim adjustment pays for itself quickly.

For performance and track-day drivers, shims also allow small amounts of extra negative camber or positive caster within the vehicle?s adjustment range. This sharpens turn-in and improves front-end grip, at the cost of some extra inner-edge tyre wear in everyday driving.

Choosing Shim Thickness and Pack Size

Shims come in different thicknesses so the correction can be built up accurately. Thinner shims allow fine adjustment in small steps, while thicker shims make larger corrections with fewer pieces in the stack. Fewer, thicker shims are usually preferred where possible, because every additional interface in a stack is another surface that can settle over time.

Each listing shows the thickness and quantity in the pack. Smaller packs suit a single vehicle or a DIY job, while larger quantities suit alignment workshops that see the same suspension design regularly and want the right shim on the shelf at the point of use.

Before ordering, check the alignment readings and the factory adjustment chart for the vehicle, which shows how much camber or caster change each shim thickness produces at each bolt position.

Fitting Alignment Shims

Workshop Fitting

Shim adjustment is normally carried out on a calibrated alignment machine. The usual sequence is to set caster first, then camber, and finally toe, because changes to caster and camber both affect toe. The pivot shaft bolts are loosened just enough to slide shims in or out, the bolts are torqued to the manufacturer?s specification, and the readings are checked again before the vehicle leaves the bay.

Mating faces on the chassis bracket and pivot shaft should be clean and free of rust scale so the shim stack clamps flat. Shims should be matched in thickness and condition, with damaged or distorted shims replaced rather than reused.

DIY Considerations

Experienced home mechanics can change shims during a bush or control arm replacement, but a professional wheel alignment is still essential afterwards. Changing shims without measurement equipment can easily make geometry worse, and incorrect toe in particular can scrub out a set of tyres in a short distance. If you are unsure of the correct stack, record the original shim positions before removing anything and refit them as a starting point.

Limitations and Trade-Offs

Alignment shims correct geometry within the limits of the suspension design. They cannot straighten a bent control arm, chassis bracket or steering component, and they will not hide worn ball joints, tie rod ends or bushes. Worn parts allow the geometry to move under load, so any alignment set on a tired suspension will drift again quickly. Inspect and replace worn components before shimming.

Very large shim stacks can reduce bolt thread engagement and clamp security, so check the maximum stack recommended for the vehicle. If the required correction exceeds that limit, it usually points to damage or a modification that needs a different solution. Extra caster increases steering effort slightly, and aggressive camber settings trade straight-line tyre life for cornering grip. Re-check the alignment after the first few hundred kilometres, as new bushes and shim stacks can settle.

Compliance and Roadworthiness

Wheel alignment settings affect how a vehicle steers and brakes, so any adjustment should keep the vehicle safe and within the standards that apply where it is registered. In Australia, requirements vary between states and territories; in the UK and Europe, suspension and steering condition is checked at the MOT or periodic roadworthiness inspection. Settings outside the factory range for performance use may need to be declared, and it is good practice to tell your insurer about any suspension modification.

Built on Nolathane Suspension Experience

Nolathane has been making polyurethane suspension bushings since 1974, originally developed to replace brass bushes in hillclimb competition. More than 50 years later, the same focus on accurate, durable suspension geometry carries through to every part in the range.

Shim adjustment works hand in hand with the bushes at the control arm pivot. Nolathane polyurethane bushes are made in a range of durometers selected for each application, and they are mechanically fitted with minimal crush and a lubricated centre sleeve so the arm pivots freely without the twisting load of bonded rubber. That stability helps the camber and caster you set with shims stay where you put them, while the material?s abrasion resistance, tensile strength and resistance to oil, grease, ozone and weathering keep the pivot consistent for the long haul.

Warranty and Support

Nolathane wheel alignment shims are backed by Nolathane?s warranty, and our fitment guarantee means the shims you order match the application shown in the listing. If your needs change, a 60-day returns window gives you time to sort it out. Our local support team can help you work out shim selection, stack sequence and related parts, whether you are repairing worn suspension, replacing components or fine-tuning geometry for performance.

Shop Wheel Alignment Shims

Shims matched by size rather than vehicle are found in Nolathane's universal parts range.

Choose the shim thickness and pack size that suits your alignment job, then order online with fast shipping straight to your workshop or garage. With accurate camber and caster correction in hand, you can set the front end to specification, protect your tyres and restore confident, straight-line steering.