Kenworth AirGlide shims are precision parts that restore ride height, balance load distribution, and return steering geometry to spec for smoother, safer operation and longer component life.
Why AirGlide shims matter
- Restore designed ride height to maintain proper air spring preload and prevent bottoming or overextension.
- Balance axle loads so bearings, tires, and suspension components share forces evenly.
- Correct caster and toe drift when small height or seat variations shift steering geometry.
- Avoid costly replacements by correcting tolerance and wear issues without swapping heavy components.
Common AirGlide shim types and where they’re used
- Flat spacer shims used between spring seats and axle or beam to change ride height in fine increments.
- Wedge and tapered shims used at control arm or knuckle seats to adjust caster and steering axis inclination.
- Torque arm and centering shims used at torque rod mounts to eliminate lateral offset and thrust angle.
- Load‑spreader plates and washers used under thin shims to prevent crushing at concentrated load points.
Technician installation workflow
- Document baseline: record ride height, alignment numbers, and take ruler‑inset photos of tire wear and shim seats.
- Inspect seating surfaces and shims: replace any shims with burrs, corrosion, or deformation; ensure seats are clean and flat.
- Measure target movement: determine required thickness change from spec or conversion chart before selecting shims.
- Install one change at a time: fit the chosen shim or stack, use load spreaders where needed, torque fasteners to OEM values, and re‑measure.
- Validate under load: road test with representative payload, then re‑measure ride height and alignment; document final shim stack with ruler photo.
QA checklist and common failure modes
- QA checklist
- Visual: shim faces flat; no rust, nicks, or burrs.
- Measurement: caliper‑checked shim thickness and alignment numbers within spec.
- Torque: fasteners to OEM torque and rechecked after run‑in.
- Documentation: ruler‑inset photos and recorded shim stacks in vehicle history.
- Failure modes
- Crushed shims from point loads when no spreader plate is used.
- Creep and corrosion from wrong alloy selection or exposed environments.
- Stacking errors when multiple shim changes are made without intermediate measurements.
- Shifted shims from reused, stretched hardware or incorrect torque sequence.
Shop best practices and quick wins
- Stock labeled AirGlide shim kits by thickness and common stack combos for Kenworth models.
- Keep a simple conversion chart at each alignment station showing shim thickness vs ride‑height or angle change.
- Enforce the one‑variable‑change rule: change only one shim stack between measurements.
- Require ruler‑inset photos for shim seats and final stacks on every job for QA and warranty defense.
- Use load spreaders and replace locking hardware when shims are exposed to high compressive loads.
Treat AirGlide shims as precision alignment components and follow disciplined measurement, installation, and documentation practices to deliver smoother rides, longer tire and bearing life, and fewer comebacks.
