How does a differential work?

One of the most important parts of a 4×4 is it’s differential, but not many people understand what it does and why you need it.

This subject has been written about over and over, so I’m not going to do that again. What this page is, is a collection of the best information I have found on the internet about the workings of a differential.

This video is about 70 years old, but it is the most complete explanation I have ever seen. For the first 2 minutes it looks like you are watching the wrong thing, but be patient, the info is coming.

The “How Stuff Works”  website has some very clear explanations:

Intro to differentials.

How differential work.

Open differentials.

Differentials and traction.

Clutch type Limited Slip Differential.

Viscous Coupling.

Locking and Torsen differentials.

Wikipedia also has very good information on differentials.

Wikipedia – Limited Slip Differential

Wikipedia – Locking Differential

Here are some videos of diff-lock demonstrations:

These videos show a great comparison between a limited slip diff, traction control and diff-locks.