What is a Dodge Anti-Spin Rear?by Renee Booker
Various types of differentials can be classified as "anti-spin." These include limited slip, locking and spool differentials. Each performs differently on and off the road. Generally, only limited slip differentials are installed in factory vehicles; however, it's possible your Dodge vehicle could be equipped with a locking or spool-type differential for off-road or racing use.
The purpose of a differential is to allow the rear wheels on a vehicle to turn at different speeds when executing a turn. The differential also allows the wheels to "lock up" or turn together at the same rate under low-traction conditions. If the wheels were locked together at all times, the vehicle would not be able to turn because the wheels on the inside of a turn spin at a different speed than on the outside of the turn. In effect, the differential stabilizes your Dodge and offers an anti-spin effect for maneuverability and safety.
Limited Slip Differentials
Limited slip differentials are widely used in four-wheel-drive and racing vehicles because they offer superior traction abilities, both on pavement and off-road. A limited slip differential allows the vehicle's wheels to turn at slightly different speeds while executing a turn but locks the axles and wheels together when the rotation ratio variance is too high. This differential allows the vehicle to turn safely in high-grip conditions such as on roadways and also allows the axles to be locked together when one wheel spins freely in a low-grip situation.
A locking differential is just what the name implies; it locks the wheels together. The main difference between a limited slip and a locking differential is that the latter can be manually locked and remains locked until manually disengaged. These differentials are primarily for off-road and racing use and should never be engaged on a public roadway or similar high-traction surface; doing so could seriously damage the drive system.
Spool-type differentials are used to permanently lock axles together. Once a spool is installed in a differential, the wheels are permanently joined together. A spool can only be removed by completely disassembling the differential housing. These differentials are only installed in racing and off-road vehicles that will never be driven on public roadways.
- diff image by Dominique LUZY from Fotolia.com