Differentials have a long history that many believe dates back to the 1st millennium BC and recorded by China.
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| 4 Different Types of Differentials |
Although they didn't have cars back then, chariots, wagons, and carts still encountered the problem of wheels spinning and dragging around corners, damaging wheels, axles, and roads. To prevent this, a simple differential was invented.
Types of differentials in cars and trucks
1 - Open Differential
This type of differential is the most basic and only allows for variations in speed or slip of individual wheels, but that's it. Under optimal road conditions, it allows the outside wheel to turn faster than the inside wheel. The problem arises when road conditions are less than ideal, such as on wet pavement, ice, snow or gravel.
With an open differential, the driving torque is still transferred even if the wheel has no traction, so the spinning tire will simply turn and go nowhere.
Open differentials are found in most vehicles on the road today, generally speaking, the cost to repair the differential is less than other types of differentials (if the same axle).
2 - Limited Slip Differential
Under ideal road conditions, a limited-slip differential acts like an open differential and transfers torque independently to each wheel.
But in tight turns or under heavy acceleration where an open differential would typically cause a tire to slip, a limited-slip differential prevents the normal amount of torque from going to the tire that is slipping (the one with the least resistance).
It does this through the use of clutches and plates in the differential. This allows the vehicle to get through corners that a vehicle with an open differential would have trouble with.
3 - Locking Differential
Found on many off-road vehicles and some performance cars, locking differentials use clutches and springs to activate a lock that sends an equal amount of power to each wheel regardless of the traction situation. This essentially creates a fixed axle.
The advantage is the ability of the locked differential to get a greater amount of traction since the total amount of torque is always available to one wheel and is not limited by the lower traction of one wheel.
At higher speeds, this is a disadvantage, but when off-roading or climbing, it is a big advantage.
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4 - Torque Vector Differential
The most complicated and advanced type of differential, a torque vectoring differential uses a collection of sensors and electronics to get data from various things (road surface, throttle position, steering system, etc.) to activate electronically controlled clutches and a controller.
Also known as active differentials, they work in the most efficient way, resulting in a truly dynamic and high-performance driving experience. Torque vectoring differentials can be found in some rear-wheel drive and high-performance all-wheel drive vehicles.
How a differential works
All vehicles have a front or rear differential as part of the axle assembly. A front wheel drive car will have a front differential while a rear wheel drive car will have a rear differential.
If the vehicle is equipped with 4-wheel drive, it may have both front and rear differentials.
A differential can be defined as a gearbox that has 3 common components: Side Gear, Ring Gear and Pinion Gear. Its job is to drive a pair of wheels on an axle but allowing them to turn at different speeds.
This is necessary when your car is turning on the road. When you make a turn, the outside wheel must cover a longer distance than the inside wheel, so the outside wheel must turn faster. The differential makes this possible.
Front engine/rear drive type (FR)
Engine → Transmission → Drive shaft → Rear differential → Axle shaft → Rear wheels
Front engine type/front wheel drive (FF)
Engine → Transaxle and integrated front differential → Front wheels
4-wheel drive
Engine → Transmission → Transfer case → Front and rear driveshaft → Front and rear differential → Front driveshaft and rear axle shaft → Front and rear wheels
Based on the above information, the front engine / front wheel drive configuration uses a front differential integrated with the transmission / transaxle. This means that the cost to repair this configuration is often more expensive than others.
To repair the differential, the transaxle must also be lowered and removed.