Included angle combines Steering Axis Inclination and camber on the same wheel. It is not normally adjusted directly; it is used to understand whether the wheel and steering pivot remain in the intended relationship.
Included angle is derived from SAI and camber.
It helps distinguish wheel inclination from steering-pivot position.
Side-to-side comparison is often more useful than the absolute number.
Interpretation must follow the suspension design and sign convention.
How included angle is formed
Viewed from the front, SAI inclines inward from vertical while camber describes the wheel inclination. The aligner combines the two values according to its sign convention and displays included angle. The result represents the angular relationship between the steering axis and the wheel plane.
Because camber can be adjustable while SAI normally is not, included angle provides a stable diagnostic reference when a technician is deciding whether an unusual camber reading comes from adjustment or from damaged geometry.
Reading diagnostic patterns
| Observed pattern | What it can suggest |
|---|---|
| Camber changed; SAI stable | Camber adjuster position or wheel-supporting component. |
| SAI changed; camber changed oppositely | Mounting-point or pivot displacement may preserve included angle. |
| Included angle differs greatly side to side | Bent knuckle, strut, control arm or incorrect component possible. |
| Both sides shifted similarly | Check ride height, loading, vehicle selection and sweep procedure. |
Using included angle in component diagnosis
Suppose one front wheel has excessive negative camber. If SAI is close to the opposite side but included angle differs, the wheel-supporting part or camber adjustment deserves attention. If both SAI and camber move in opposite directions while included angle remains similar, a mounting point or subframe position may have shifted.
Measurement quality
Included angle depends on a reliable SAI calculation, so caster-sweep quality matters. Make sure the turn plates move freely, the wheels reach the requested angles and the targets remain visible. Repeat the sweep when the diagnostic pattern conflicts with the physical inspection.
Wheel and clamp runout should also be compensated before the sweep. A repeatable measurement is more valuable than a single precise-looking number.
Repair verification
After replacing a suspected component or repositioning a subframe, repeat compensation if any target was disturbed, perform a fresh sweep and compare SAI, camber and included angle side to side. Then complete normal caster, camber and toe adjustment. Document the before-and-after diagnostic values when the repair was related to impact damage.
Frequently asked questions
Is included angle adjustable?
Not directly. It changes when camber is adjusted or when the position of steering-axis components changes.
Can included angle identify a bent steering knuckle by itself?
No. It can support that diagnosis, but the technician should compare SAI, camber, setback, ride height and physical measurements.
Why might included angle differ after a camber adjustment?
Camber is one part of the included-angle relationship. Changing camber changes the included angle even if SAI remains stable.
Technical content reviewed for TreadPlus Learn v1.0 · Updated July 16, 2026
SureAlign feature: See how SureAlign presents and uses this measurement →