Center axle disconnect
Encyclopedia
A center axle disconnect system or CAD is an alternative to locking hubs
. CAD systems are typically used in front drive axles on four wheel drive
vehicles. A CAD system works by having an axle shaft (typically the longer shaft) split into two pieces. One piece is connected to the carrier, the other connected to the wheel. This reduces drag on the axle by allowing only the spider and side gears to spin, while the carrier, pinion and drive shaft are at rest. The axle is engaged by connecting the two split axle shafts. The ends of the axles are typically splined and use a collar to connect the two shafts together by sliding over both shafts.
Like locking hubs, the CAD system is designed to improve fuel efficiency of the vehicle. Other, often debated, benefits of CAD systems are reduced vibration, axle wear, and noise, as well as improved steering and drivability.
Locking hubs are obtrusive and damage can occur that can cause the four wheel drive system to fail — damage that would not be an issue in a CAD system. However CAD systems are mostly vacuum controlled and damage can occur to the vacuum system and to the CAD itself. Rotting of vacuum lines will cause the four wheel drive system to fail — damage that would not be an issue with locking hubs.
----
Locking hubs
Locking hubs, also known as free wheeling hubs are an accessory fitted to many four-wheel drive vehicles, allowing the front wheels to be manually disconnected from the front half shafts....
. CAD systems are typically used in front drive axles on four wheel drive
Four Wheel Drive
The Four Wheel Drive Auto Company, more often known as Four Wheel Drive or just FWD, was founded in 1909 in Clintonville, Wisconsin, as the Badger Four-Wheel Drive Auto Company by Otto Zachow and William Besserdich.-History:...
vehicles. A CAD system works by having an axle shaft (typically the longer shaft) split into two pieces. One piece is connected to the carrier, the other connected to the wheel. This reduces drag on the axle by allowing only the spider and side gears to spin, while the carrier, pinion and drive shaft are at rest. The axle is engaged by connecting the two split axle shafts. The ends of the axles are typically splined and use a collar to connect the two shafts together by sliding over both shafts.
Comparison with locking hubs
Although a widely used system, this system is not as efficient as a system with locking hubs. A CAD system spins the axle shafts, spider and side gears in the carrier during normal driving. Locking hubs disengage the axle at the wheels, allowing all of the axle to be at rest during normal driving. Not as an efficient as locking hubs, a CAD system still makes for much less drag than having the axle completely locked in.Like locking hubs, the CAD system is designed to improve fuel efficiency of the vehicle. Other, often debated, benefits of CAD systems are reduced vibration, axle wear, and noise, as well as improved steering and drivability.
Advantages and disadvantages
Unlike locking hubs, CAD systems are generally automatic and engaged when the vehicle is placed in four wheel drive. Due to the lack of driver control over the CAD, it is not as well known to the public as locking hubs are.Locking hubs are obtrusive and damage can occur that can cause the four wheel drive system to fail — damage that would not be an issue in a CAD system. However CAD systems are mostly vacuum controlled and damage can occur to the vacuum system and to the CAD itself. Rotting of vacuum lines will cause the four wheel drive system to fail — damage that would not be an issue with locking hubs.
External links
- http://www.4x4wire.com/dodge/tech/solid_axle_cad/
- http://www.g2axle.com/axle-gear-guide/encyclopedia-a-d.aspx
----