Shock Bushings

Nolathane shock bushings mount each end of a shock absorber to the vehicle. Every shock absorber bushing sits between the shock and its mount, letting the shock tilt as the suspension moves while keeping steel away from steel. When the bushings wear, even a brand-new shock can?t do its job properly, and the first sign is usually a knock you can?t ignore.

Polyurethane shock bushings suit trucks, SUVs, 4x4s, and passenger cars running factory or aftermarket shocks. Each listing shows the mount style, dimensions, and vehicles or shock types each bushing suits.

How Shock Absorber Bushings Work

A shock absorber controls how fast the suspension moves. Every time a wheel hits a bump, the shock resists that motion and turns it into heat. All of that damping force has to pass through the shock?s mounts, and the bushings are where it enters the frame and suspension.

The shock doesn?t move in a straight line. As the suspension travels up and down, and as the axle or control arm swings through its arc, the shock changes angle slightly. The bushing allows that angular movement without binding, so the shock body isn?t twisted or side-loaded.

The bushing also isolates vibration. Small, high-frequency movements from the road are absorbed at the mount instead of being passed straight into the body as noise.

Shock Bushing Styles

Shocks are mounted in a few different ways, and each needs its own bushing design. Each listing shows the style and dimensions.

Eye-Mount Bushings

An eye mount is a round loop at the end of the shock, with a bolt passing through it. The bushing presses into the eye around a steel sleeve. Straight bushings have a consistent outside diameter. Hourglass bushings are narrower in the middle, which lets the shock rock more freely where the mount angle changes a lot.

Stem-Mount Bushings and Washers

A stem mount uses a threaded rod at the end of the shock that passes through a hole in the mount. A pair of bushings, one on each side, clamps the mount between them, held in place by cupped washers and a nut. Stem-mount bushings are usually half bushings that work as a pair.

Universal and Vehicle-Specific Kits

Vehicle-specific kits are matched to a particular suspension. Universal kits are sized by dimension, so they suit custom builds, aftermarket shocks, and vehicles where the right part is hard to find.

Why Shock Bushings Wear Out

Shock bushings work in a harder environment than most suspension bushings. Several things speed up their wear:

• Constant articulation, because the shock changes angle with every movement of the suspension
• Heat from the shock body, which warms the bushing and ages rubber quickly
• Road grime, water, and salt thrown up by the tires
• Heavy loads and towing, which push the suspension through more travel
• Over-tightened stem nuts that squash the bushing out of shape

Signs of Worn Shock Bushings

Worn shock bushings are one of the most common causes of suspension noise. Look and listen for:

• Knocking or clunking from the shock mounts over bumps
• A rattle on rough or washboard roads
• The vehicle bouncing more than usual after a bump
• Splitting, cracking, or bushing material squeezed out of the eye
• A shock sitting off-center in its eye or mount
• New shocks that still knock, because the old bushings were reused

That last one catches many people out. A new shock fitted with tired bushings can knock as loudly as the old one did, so check the rear shock bushings and fronts whenever the shocks are replaced.

Risks of Driving on Worn Shock Bushings

A worn shock bushing does more than make noise. When the bushing allows free play, the shock has to move through that gap before it starts to damp, so the suspension loses some of its control.

The play also lets the shock eye and bolt hammer against each other. Over time, that can wear the eye oval, damage the mounting bolt, or elongate the mount on the vehicle, turning a cheap bushing job into a more expensive repair.

With less damping control, the tires bounce more on rough surfaces, which can lead to uneven tire wear. When the vehicle is loaded or towing, handling becomes less predictable, especially over dips and on uneven roads.

Rubber and Polyurethane Shock Bushings

Rubber shock bushings are the usual factory choice. They?re soft and quiet when new, but they break down faster under heat and constant movement. Once a shock rubber bushing hardens or splits, it starts to allow play.

Polyurethane shock bushings hold the shock more firmly in its mount. They resist abrasion and stand up to oil, grease, ozone, and weathering, so they last longer in the harsh conditions around a shock. The hardness grade, or durometer, is chosen so the bushing locates the shock firmly while still allowing it to articulate.

The trade-off is a little more road feel. Polyurethane passes slightly more vibration into the vehicle than soft rubber, though most drivers find the firmer, quieter mount worth it.

Measuring for Shock Bushings

Getting the right size matters, especially with universal kits. Each listing shows the dimensions to compare.

Inside Diameter

The inside diameter needs to match the mounting bolt or sleeve. Measure the bolt or the old sleeve to confirm.

Outside Diameter

The outside diameter must suit the bore of the shock eye. Measure the eye itself, not the old bushing, since a worn bushing may have shrunk or distorted.

Eye Length

Measure the width of the shock eye from face to face, so the bushing sits flush without overhanging.

OEM and Aftermarket Shock Compatibility

Aftermarket shocks don?t always use the same eye size as factory shocks. If you?re fitting new aftermarket shocks, measure them rather than relying on the vehicle?s original dimensions.

Replacing Shock Bushings

Shock bushing replacement suits a qualified installer or an experienced home mechanic. The general process looks like this:

• Support the vehicle safely with the suspension at ride height
• Remove the shock from its mounts
• Press out the old bushings, or cut them out if they?re bonded or seized
• Clean the inside of the shock eye
• Fit the new bushings and sleeve, using a polyurethane-safe grease
• Refit the shock and tighten eye-mount bolts to specification at ride height
• Tighten stem-mount nuts until the bushings are snug but not crushed
• Replace the bushings on both sides of the axle together

Check the torque again after the first few hundred miles.

Limitations and Trade-Offs

New shock bushings fix mounting problems, but they have limits:

• Polyurethane transmits slightly more road noise and vibration than rubber
• It can squeak if it isn?t greased
• New bushings can?t fix a leaking or worn-out shock
• They can?t repair a shock eye or mount that has worn oval
• Some shocks have bonded eyes that can?t be rebushed

Compliance and Insurance

Make sure the vehicle meets the inspection requirements of the state where it?s registered, including lift and lowering rules if you?ve fitted aftermarket shocks. Let your insurance company know about any suspension modifications.

Warranty and Support

Nolathane shock bushings carry a lifetime warranty against manufacturing defects in material and workmanship, for the original vehicle. If you?re not sure which style or size you need, our local support team can help.

Shop Shock Bushings

Running struts rather than shocks? Use strut mount bushings for the top mount.

Find shock bushings for your vehicle, or choose a universal kit by size, and order online with fast shipping. Every part is covered by our fitment guarantee, and universal kits are guaranteed to match the dimensions shown in the listing.