Copy and paste from another post.
LOCKERS
If you want a locker, you have 3 types. Automatic, selectable, and solid.
A solid one is either a "Lincoln locker" where the spider gears are welded together and to the carrier or a full spool that serves the same purpose and replaces the carrier or a mini spool that just replaces the spiders.
An automatic locker is one that has a ratcheting mechanism in it so that it can slip when you’re turning and are not on the gas and will lockup as soon as you give it gas. Lock-right, Detroit and Aussie all make automatic lockers. Most automatics replace the spiders but one of the two that Detroit makes replaces the carrier.
A selectable locker is one that you can turn on and off like the e-locker in your titan. The one made my OX is manual and has a shift lever that mounts in the cab. ARB lockers are operated by air. This means that they need some type of compressor to go with them. E-lockers are electronically operated. Then there is the Ected locker/limited slip which is made by Auburn. This one is again an electric locker but it also has the L/S feature when unlocked.
Lockers are not cheap though. Welding or spooling is the cheapest but if you have a daily driver then you will not want to do either of those. Automatics are about 200-300 dollars and a lot of people like them for the price. Selectable are really nice but they are expensive both in initial cost, 600-900 dollars and in the installation cost because the gears need to be set up again because selectable lockers replace the carrier. Gear setup can be 150-300 dollars.
