What are stabilizer bar bushings and how do they work?
Stabilizer bar bushings are rubber bushings designed to isolate the steel stabilizer bar from the vehicle frame and suspension. The stabilizer bar itself is typically connected to the lower control arms or another suspension component. Through a twisting action, the bar counteracts vehicle lean as you turn around a corner. Cars may be equipped with just a front stabilizer bar or both front and rear stabilizer bars.
When to consider replacing stabilizer bar bushings:
- Knocking, clunking, grinding or squeaking noises. If a bushing has failed, the type of noise you hear depends on the location and extent of the failure. Complete loss of the bushing will cause metal-to-metal contact; you might hear clunking or grinding. If the bushing has dried out and is hard, you might hear squeaking.
- Visible physical damage. On visual inspection, the bushings may be cut, abraded, dislodged, loose, or even missing.
How do mechanics replace stabilizer bar bushings?
- Raise and support the vehicle using steel safety stands
- Remove tire and wheel assemblies on both ends of the axle.
- Detach stabilizer bar bushing clamp, or stabilizer bar link, depending on the location of the bushing to be replaced. Often, if the stabilizer bushing to the vehicle frame mount is being replaced, the stabilizer bar must be completely detached at all links for there to be enough space to install the new frame bushings.
- Once all bushings and required hardware are replaced, the bushing mounts are tightened with a load on the suspension. If required by the service manual, this step ensures the bushings will be in an unloaded condition and not pinched when the vehicle is sitting at normal ride height.
- The vehicle is lowered and road tested to ensure normal cornering; meaning body lean within acceptable limits and without noise.
Is it safe to drive with a stabilizer bar bushings problem?
Yes. Although not a severe threat, aside from the likely presence of noise, operation at highway speeds when performing sudden maneuvers can be affected — especially if the vehicle is carrying a heavy load. Seek repair at your earliest convenience.
When replacing stabilizer bar bushings keep in mind:
- The mechanic will inspect the stabilizer bar itself for corrosion, cracks and accident damage.
- Bushings are sold in pairs because it is recommended they be replaced in pairs.
- Always have all bushings inspected, including the bushings in the stabilizer bar links, even if just the stabilizer bar frame mount bushings are replaced.
- Removal and re-attachment of the stabilizer bar, and replacement of the bushings, normally has no effect on wheel alignment.