Q: What Are Sprung And Unsprung Weight And Why Do They Matter?

asked by on

What are sprung and unsprung weight and why do they matter?

First, we will discuss unsprung weight. Unsprung weight, when considering the automobile, is the mass of the vehicle’s suspension system. To make this clear, the unsprung weight has to do with the vehicle’s suspension system, the part of the vehicle that supports the chassis and drives the wheels into contact with the ground. Unsprung weight usually includes the wheels and anything directly connected to them. You may consider a portion of the struts, braking system, axles, wheel bearings, and vehicle control arm assemblies when speaking of unsprung weight.

The mass of these items is not supported by the suspension system and is the unsprung portion of the vehicle’s total mass. When observing a vehicle traveling over a bump, the vehicle’s chassis seems to rock while the wheels and tires remain in contact with the road. The portion of the vehicle that does not rock is unsprung mass, while the moving chassis represents the sprung mass of the vehicle.

Sprung mass represents the portion of the vehicle’s weight that is supported by the suspension system. The sprung mass includes the vehicle’s chassis and anything directly fastened to it that is able to move while the unsprung mass does not. You may consider the seats inside the vehicle, the engine and transmission assembly, and a portion of the drivetrain as sprung weight.

Unsprung and sprung mass are very important when considering ride comfort and vehicle traction control.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. What Are Sprung And Unsprung Weight And Why Do They Matter?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: What Can Cause a Vehicle's Suspension To Collapse

The suspension on your vehicle is comprised of many different components. Any of these components can fail at any time, but most suspension parts will fail slowly over time. If you have a sudden change in the way that your...

Q: Suspension stiff

Generally suspension components will not get stiffer unless there is something in the suspension system that is seized or damaged. A full inspection of the suspension system should be carried out. Loose steering on the other hand generally happens when...

Q: Cabin air filters on a 2010 Altima

Most of them actually do come with some kind of the tray. Maybe yours is lost and you need to get another one. But they do generally have arrows this side up or air flow downwards that show you which...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.