How to Measure an Automotive Wheel Bolt Pattern
Knowing how to measure a wheel bolt pattern is essential when purchasing aftermarket wheels, wheel spacers, adapters or replacement hubs. An incorrect bolt pattern can prevent the wheel from mounting properly and may create a serious safety risk.
Fortunately, you can determine most automotive bolt patterns with a tape measure, ruler or caliper.
What Is a Wheel Bolt Pattern?
A wheel bolt pattern—also called a bolt circle, lug pattern or pitch circle diameter (PCD)—is identified by two measurements:
- The number of lug holes or wheel studs
- The diameter of the imaginary circle passing through the center of those holes or studs
For example, a 5x114.3 bolt pattern has five lug positions arranged on a circle measuring 114.3 millimeters in diameter.
Bolt patterns may be listed in either millimeters or inches. For example:
- 5x114.3mm is also commonly called 5x4.5"
- 5x127mm is also called 5x5"
- 6x139.7mm is also called 6x5.5"
- 8x165.1mm is also called 8x6.5"
Tools Needed to Measure a Bolt Pattern
You can measure a wheel bolt pattern using:
- A tape measure
- A straight ruler
- A digital or dial caliper
- A wheel bolt-pattern gauge
A caliper or dedicated bolt-pattern gauge will generally provide the most accurate measurement.
How to Measure a 4-Lug Bolt Pattern
A four-lug wheel is one of the easiest patterns to measure.
Measure from the center of one lug hole or wheel stud directly across to the center of the opposite lug. This measurement is the bolt-circle diameter.
If the distance is 100 millimeters, for example, the bolt pattern is 4x100.
How to Measure a 5-Lug Bolt Pattern
A five-lug pattern requires a different method because no lug is positioned directly opposite another.
Measure from the center of one lug hole or stud to the outside edge of the lug hole or stud located farthest away. Be sure to measure across the center of the wheel rather than diagonally between neighboring lugs.
This method provides a practical bolt-pattern measurement, but five-lug patterns can be difficult to identify accurately with a basic tape measure. A bolt-pattern gauge or caliper is recommended when distinguishing between similar sizes such as 5x114.3 and 5x115.
Common five-lug patterns include:
- 5x100
- 5x108
- 5x110
- 5x112
- 5x114.3
- 5x115
- 5x120
- 5x120.7
- 5x127
- 5x135
How to Measure a 6-Lug Bolt Pattern
To measure a six-lug wheel, measure from the center of one lug hole or stud directly across to the center of the opposite one.
A measurement of 139.7 millimeters indicates a 6x139.7 bolt pattern, which is also commonly referred to as 6x5.5".
How to Measure an 8-Lug Bolt Pattern
An eight-lug bolt pattern is measured from the center of one lug hole or wheel stud to the center of the lug directly opposite it.
Common eight-lug bolt patterns include:
- 8x165.1, also called 8x6.5"
- 8x170
- 8x180
- 8x200
- 8x210
Do not assume that every eight-lug truck uses the same bolt pattern. Vehicle manufacturers use several patterns that may appear similar but are not interchangeable.
Measuring a Wheel Versus a Vehicle Hub
You can determine a bolt pattern by measuring either the wheel or the vehicle hub.
When measuring a wheel, measure the lug holes using the appropriate method for the number of holes. When measuring a vehicle, use the wheel studs or threaded bolt holes on the hub.
The wheel and vehicle must have matching bolt patterns unless a properly designed wheel adapter is being used.
Inch-to-Millimeter Bolt-Pattern Conversions
Some bolt patterns are described in inches while others are listed in millimeters. To convert inches to millimeters, multiply the inch measurement by 25.4.
| Inch Measurement | Metric Measurement |
|---|---|
| 4.00" | 101.6mm |
| 4.25" | 107.95mm |
| 4.50" | 114.3mm |
| 4.75" | 120.65mm |
| 5.00" | 127mm |
| 5.50" | 139.7mm |
| 6.50" | 165.1mm |
Be careful with rounded measurements. A pattern listed as 5x120 is not necessarily interchangeable with 5x4.75, which equals approximately 5x120.7.
Bolt Pattern Is Only Part of Wheel Fitment
A matching bolt pattern does not guarantee that a wheel will fit the vehicle. Several other specifications must also be checked:
- Wheel center-bore diameter
- Vehicle hub diameter
- Wheel offset
- Wheel width and diameter
- Brake and suspension clearance
- Lug-nut or lug-bolt thread size
- Lug-seat style
- Stud length and thread engagement
- Vehicle load requirements
If the wheel’s center bore is larger than the vehicle hub, the correct hub-centric rings may be needed to center the wheel properly. Wheel spacers or adapters must also match the vehicle, wheel and intended application.
Common Bolt-Pattern Measuring Mistakes
Avoid these common errors:
- Measuring from the edges instead of the centers on an even-lug pattern
- Measuring between neighboring lugs
- Confusing inches with millimeters
- Assuming visually similar patterns are interchangeable
- Rounding a measurement to the nearest common size
- Checking the wheel pattern without verifying the vehicle pattern
- Assuming a matching bolt pattern means the wheel will fit
Confirm the Pattern Before Ordering
Always confirm the bolt pattern using the vehicle manufacturer’s specifications, a reliable fitment guide or a professional installer before ordering wheels, spacers, adapters or related hardware.
Accurate measurements help ensure that you receive components designed for your application. When in doubt, contact Lug Nut Guys with your vehicle’s year, make, model, drivetrain and wheel information for help selecting the correct wheel hardware.
Torque Yer Nuts—and verify the fit before hitting the road.