Here’s a detailed explanation of the different types of differentials in automobiles:
In this article:
Types of Differentials
What is a Differential?
A differential is a mechanical device that allows wheels on the same axle to rotate at different speeds while transmitting torque from the engine.
Differentials can be classified based on mechanical design and torque distribution.
1️⃣ Open Differential
- Description:
- Most basic and common type.
- Uses spider (planet) gears and side (sun) gears to allow wheel speed differences.
- Operation:
- Torque is split equally between the two wheels.
- Wheels can rotate at different speeds during turns.
- Advantages: Simple, reliable, inexpensive.
- Disadvantages:
- Torque always goes to the wheel with least traction.
- Poor off-road or slippery road performance.
Also read: What is open differential?(in detail).
2️⃣ Limited-Slip Differential (LSD)
- Description:
- Allows some difference in wheel speed but limits excessive slip.
- Improves traction on slippery surfaces.
- Types:
- Clutch-type LSD: Friction plates transfer torque to wheel with traction.
- Torsen / Helical LSD: Uses gears to bias torque automatically.
- Viscous LSD: Uses viscous fluid to resist speed difference.
- Advantages: Better traction than open differential, improves cornering stability.
- Disadvantages: More complex and expensive; may require maintenance.
3️⃣ Locking Differential
- Description:
- Can lock both wheels together to rotate at the same speed.
- Prevents slip completely.
- Types:
- Manual locking differential: Driver engages lock via lever or switch.
- Automatic locking differential: Locks automatically when one wheel slips.
- Advantages: Excellent traction in off-road conditions.
- Disadvantages: Harder to steer when locked; not ideal for normal roads.
Also read: What is Locking differential?(in detail).
4️⃣ Torque-Vectoring Differential
- Description:
- Electronically or hydraulically controls torque distribution.
- Can send more torque to the wheel with better grip during cornering.
- Advantages: Improves handling, cornering stability, and traction.
- Disadvantages: Complex, expensive, often used in AWD or performance vehicles.
Also read: What is Torque vectoring differential?(in detail).
5️⃣ Spool or Solid Axle (Non-Differential)
- Description:
- Not technically a differential; locks both wheels together permanently.
- Operation:
- Both wheels rotate at the same speed.
- Advantages: Maximum traction in off-road or racing applications.
- Disadvantages: Difficult to steer, causes tire scrub and increased wear on turns.
✅ Summary Table of Differential Types
| Type | Torque Distribution | Advantages | Disadvantages | Common Use |
|---|---|---|---|---|
| Open | Equal, wheels can rotate at different speeds | Simple, reliable | Poor traction if one wheel slips | Standard cars |
| Limited-Slip (LSD) | Partial slip allowed, torque biased | Better traction, improved cornering | More complex, costlier | Performance cars, AWD, trucks |
| Locking | Both wheels locked together | Excellent off-road traction | Hard to steer, not ideal on road | Off-road vehicles |
| Torque-Vectoring | Torque actively controlled between wheels | Superior handling, cornering stability | Complex, expensive | AWD/performance vehicles |
| Spool / Solid | Wheels rotate at same speed | Maximum traction | Tire scrub, hard steering | Racing, off-road applications |
6️⃣ Applications
- Open differential: Most passenger cars.
- LSD: Sports cars, performance sedans, trucks for better traction.
- Locking differential: Off-road 4x4s, tractors, heavy-duty vehicles.
- Torque-vectoring: Modern AWD sports cars and SUVs.
- Spool: Racing vehicles, extreme off-road setups.
Other courses:
