Camber, Caster & Kingpin Gauge
00 · About this guide
Contents.
- 01Order of adjustment01
- 02Understanding caster · Measure caster angle02-03
- 03Understanding camber · Measure camber angle04-05
- 04Understanding kingpin inclination · Measure kingpin inclination06-07
- 05Maintenance08
- 06Warranty09
D · LevelB · Caster GaugeA · Camber GaugeC · Kingpin Inclination Gauge01 · Before you start
Order of adjustment.
Set caster first, then camber, then toe last.
Caster
Camber
Toe
Mount the gauge
Place the gauge on the adapter plate of any AutoSolo wheel clamp, with the gauge’s locator pin aligned to the center of the plate, or on a flat surface parallel to the wheel hub’s plane.
02 · Caster
Understanding caster.
Caster is the forward or rearward tilt of the steering axis when viewed from the side of the vehicle.
0°A rearward tilt is positive caster, while a forward tilt is negative caster.
Caster directly influences steering stability and how well the wheels return to center after a turn. Too little caster can make the vehicle wander and feel unstable, while too much caster can make steering heavy or difficult.
Correct caster provides straight-line stability, improved handling, and reduced driver fatigue.
Measure caster angle
Note: Alignment Turntables (ASWG008 or ASWG004) are required for this measurement, to turn your wheels a measured 20° in and out.
Drive onto turn plates
02 · Caster
Measure caster angle.
Note: Alignment Turntables (ASWG008 or ASWG004) are required for this measurement, to turn your wheels a measured 20° in and out.
Drive onto turn plates
Initial wheel turn, 20° outward
Turn the wheel 20° OUT. Verify against the turn plate degree scale.
Level the gauge
Recheck and re-center Torpedo Level D, if needed, to hold the reference plane true.
Zero the gauge
Adjust the knob beneath Torpedo Level B until the bubble aligns at 0 degrees. This sets your starting reference point.
Final wheel turn, 20° inward
Turn the wheel 40° total to 20° IN. Verify against the turn plate degree scale.
Re-level if needed
Confirm Torpedo Level D is still centered after repositioning.
Read the caster swing
Read the Caster swing from Torpedo Level B. This is how far camber moved across the 40° sweep. Step 08 converts it to caster.
Convert to caster angle
03 · Camber
Understanding camber.
Camber is the inward or outward tilt of a wheel when viewed from the front of the vehicle.
0°Tire Center LineVerticalCamberA wheel tilted inward at the top has negative camber, while a wheel tilted outward has positive camber.
Proper camber ensures the tire tread contacts the road evenly, which maximizes grip, especially during cornering. Incorrect camber can cause uneven tire wear, reduced traction, and poor handling.
Keeping camber within manufacturer specifications ensures predictable performance and longer tire life.
Measure camber angle
Align wheels to straight-ahead position
03 · Camber
Measure camber angle.
Align wheels to straight-ahead position
Mount the gauge
Level the gauge
Read camber angle
04 · Kingpin inclination
Understanding kingpin inclination.
Kingpin Inclination (KPI), also known as Steering Axis Inclination (SAI), is the inward tilt of the steering pivot axis when viewed from the front.
KPI works in combination with caster to keep the wheels self-centering and to provide stability while driving straight. This angle reduces steering effort and helps the vehicle maintain proper tracking.
If KPI is out of specification, it can cause pulling to one side, uneven tire loading, and steering that feels inconsistent.
Ensuring proper KPI alignment improves both safety and driver comfort.
Measure kingpin inclination
Drive onto turn plates
Drive onto turn plates
Initial wheel turn, 20° outward
Turn the wheel 20° OUT. Verify against the turn plate degree scale.
Level the gauge
Check and center Torpedo Level D to maintain a true reference plane.
Zero KPI gauge based on side of vehicle
If working on the left side, adjust the knob beneath Torpedo Level C until the bubble aligns at 0 degrees on the Left Indicator. If working on the right side, align to 0 degrees on the Right Indicator.
Final wheel turn, 20° inward
Turn the wheel 40° total to 20° IN. Verify against the turn plate degree scale. Do NOT re-center Torpedo Level D before Final Reading.
Read kingpin inclination (KPI)
Read the KPI angle from Torpedo Level C. This represents the inward tilt of the steering pivot axis.
Note: Level D will sit off center after the sweep. That offset is the measurement, so leave it.
05 · Care
Maintenance.
To keep the gauge reading true and in service, it should be regularly inspected, cleaned, and stored properly.
Cleaning
- After each use, wipe the gauge body and magnetic base with a clean, dry cloth.
- If debris or metal shavings are present on the magnet, carefully remove them with a soft brush or cloth.
- Do not use solvents, harsh chemicals, or abrasive pads, as these may damage the surface finish or calibration markings.
Handling & storage
- Always handle the gauge with care. Avoid drops, impacts, or excessive force on the dial or vial.
- Store the gauge in its protective case when not in use to prevent damage and dust buildup.
- Keep the tool in a dry environment to avoid corrosion, especially around the magnetic base.
General use tips
- Do not disassemble the gauge, as this can compromise calibration.
- Avoid exposing the tool to extreme temperatures or moisture, which can affect performance.
- Inspect regularly for signs of wear or damage. Replace immediately if functionality is compromised.
06 · Warranty
Warranty.
Limited 1-year replacement warranty
AutoSolo warrants the Camber, Caster, KPI Gauge to be free from manufacturing defects for one year from the original retail purchase date. This warranty is non-transferable and ends if the product is sold or transferred.
What we cover
If a defect is found within the warranty period and the product has been used as directed, AutoSolo will repair or replace the product at its discretion. Any replacement is covered only for the remainder of the original warranty term.
What’s not covered
- Abuse, misuse, neglect, or accidents
- Alteration or modification
- Shipping damage
- Improper installation, use, or maintenance
- Use of non-AutoSolo parts
- Damage from natural disasters or force majeure events
How to claim
- Email support@autosolotools.com within 30 days of discovering the defect.
- Include proof of purchase and photos of the defect.
- Wait for return authorization before shipping anything back.
This warranty does not affect your statutory rights.