---
title: suspensionStiffness
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnphysicsvehiclewheel/suspensionstiffness
---

# suspensionStiffness

The spring coefficient of the suspension between the vehicle and the wheel.

## Declaration

```swift
var suspensionStiffness: CGFloat { get set }
```

## Discussion

Discussion The spring coefficient determines both how quickly the wheel returns to its natural position after a shock (for example, when the vehicle runs over a bump) and how much force from the shock it transmits to the vehicle. The default spring coefficient is 2.0.

## See Also

### Simulating Suspension

- [suspensionCompression](scenekit/scnphysicsvehiclewheel/suspensioncompression.md)
- [suspensionDamping](scenekit/scnphysicsvehiclewheel/suspensiondamping.md)
- [maximumSuspensionTravel](scenekit/scnphysicsvehiclewheel/maximumsuspensiontravel.md)
- [maximumSuspensionForce](scenekit/scnphysicsvehiclewheel/maximumsuspensionforce.md)
- [suspensionRestLength](scenekit/scnphysicsvehiclewheel/suspensionrestlength.md)