What is the problem with limited slip differential?

Limited-slip differentials (LSDs) improve traction by sharing torque between wheels, but they come with trade-offs: higher cost, more complex maintenance, potential handling quirks, and reliability concerns in certain conditions.

How Limited-Slip Differentials Work

Understanding the main designs helps explain why they can be finicky or fail under stress.

• Clutch-type LSD: Uses a stack of clutch plates to limit slip between shafts. Pros: strong grip and quick response; Cons: wear over time, requires specialized lubrication with friction modifiers, potential clutch chatter, and higher service costs.


• Torsen/helical (gear-based) LSD: Uses gears to bias torque toward the wheel with more grip without clutch packs. Pros: smooth operation and low maintenance; Cons: cannot fully uncouple, can introduce understeer/oversteer bias in certain cornering conditions, and is less tunable.


• Viscous LSD: Relies on shear-thickening fluid to transfer torque. Pros: simple, quiet; Cons: slower engagement, performance degrades with heat and age, and effectiveness drops in extreme cold or when fluid wears out.


• Electronic/brake-based LSD (eLSD): Uses sensors and actuators to modulate torque, sometimes by braking one wheel to redirect torque. Pros: highly tunable and integrates with stability control; Cons: adds electronics complexity and potential points of failure, depends on software and sensor reliability.

These designs illustrate the spectrum from simple, mechanical solutions to computer-controlled systems, each with distinct benefits and drawbacks.

Where LSDs Can Cause Problems

Even well-made LSDs can create issues in real-world driving, especially when pushed hard or misapplied.

Common fault modes and how they show up

The following list highlights typical problems engineers and drivers watch for, along with what they imply about the system's condition.

• Clutch wear and uneven locking: Over time, clutch packs wear, reducing lockup force and making handling inconsistent or unpredictable during acceleration and cornering.


• Overheating and fluid issues: Friction generates heat; if oil is degraded or incompatible with the LSD design, performance suffers and seals or gears may wear faster.


• Handling changes and feel: LSDs can alter steering balance, sometimes causing understeer or oversteer depending on design, throttle input, and cornering load.


• Noise, chatter and binding: Worn clutches or mechanical wear can cause grinding, chattering, or binding, particularly at low speeds or during gear changes.


• Compatibility with ABS/traction control: LSDs interact with electronic stability programs; miscalibration or older systems can lead to unexpected braking or torque bias under heavy cornering.


• Maintenance cost and complexity: Higher service costs, needs for specialty fluids or frequent oil changes, and potential dealer-only service can raise ownership costs.

In short, LSDs deliver traction advantages when they function well, but they can demand careful maintenance, correct fluids, and awareness of how they change driving feel.

Is an LSD Right For Your Vehicle and Driving Style?

Consider how you drive, where you drive, and how much you value traction versus predictability. The choice matters most for performance or off-road applications and for drivers who push hard in corners or on slippery surfaces.

• For daily driving in mixed conditions: an LSD can improve traction, but a well-maintained open diff with good tires may be simpler and more predictable for most drivers.


• For spirited street or light track use: a clutch-type LSD provides strong grip and sharper corner exit, but requires attention to wear, fluid type, and potential noise or pedal feel.


• For winter or low-traction climates: a gear-based (Torsen) LSD can help, yet no system substitutes for proper winter tires; some designs may still struggle on ice.


• For off-road or extreme conditions: a mechanical locking differential (locker) may be preferable when full torque transfer to a single wheel is required; LSDs cap torque transfer and may not suffice in extreme surfacing.

Choosing an LSD involves balancing traction gains with maintenance, cost, and driving comfort, tailored to your climate and use case.

Summary

Limited-slip differentials offer clear traction benefits across a range of driving scenarios, from daily commutes to performance driving. However, they come with trade-offs: higher upfront and ongoing costs, more intricate maintenance requirements, potential changes to steering and throttle feel, and reliability considerations tied to design type and fluid compatibility. Understanding the design you have or are considering helps buyers, drivers, and technicians anticipate potential problems and plan appropriate maintenance and driving expectations.

What are the downsides of limited slip differentials?

The main disadvantages of a limited slip differential (LSD) are increased cost, higher maintenance needs, and potential for more uneven tire wear. LSDs are more complex and expensive than open differentials, and some types require special additives, frequent fluid changes, and have clutches that can wear out. Improperly matched tires or heavy driving can also cause premature clutch wear or jerking.
 
Cost and complexity

• Higher upfront cost: LSDs are more expensive to manufacture and purchase than open differentials. 
• Mechanical complexity: The added components make the system more complex, increasing the potential for more intricate repairs. 

Maintenance and longevity

• Increased maintenance: LSDs typically require more frequent fluid changes and sometimes special additives to keep the friction plates or clutches lubricated and functioning correctly. 
• Wear and tear: The friction components in clutch-based LSDs can wear out over time, necessitating replacement. 
• Tire wear: Uneven torque distribution can lead to more uneven wear between tires. Mismatched tire sizes (even a small difference) can cause the LSD to slip unnecessarily and accelerate wear. 

Performance and drivability

• Not 100% power to one wheel: Unlike a welded differential, an LSD limits power transfer, meaning it can't send all power to a single wheel if one has zero traction. 
• Potential for jerking: Some types of LSDs can cause jerking or noise during cornering, especially if they are set up with heavy pre-load. 
• Less effective in certain conditions: While it improves traction in many situations, some specific scenarios, like a single tire on ice, may benefit more from an open differential's "spinning" to move the vehicle. Heavy use in conditions like a wet burnout box can cause overheating and kill clutch packs. 

How long does a limited slip differential last?

LSD conversion kit can last up to 200k miles if it is installed according to the our instructions and if you use quality LSD oil such as Motul.

Which is better, limited-slip or open differential?

An LSD is better than an open differential for performance driving, as it provides better traction by sending power to both wheels, which is beneficial for high-speed cornering, accelerating, and drifting. An open differential is cheaper and sufficient for most daily driving, as it is smooth and predictable in normal conditions but will lose traction and send power to the wheel with the least grip in challenging situations.
 
Limited Slip Differential (LSD)

• How it works: It limits the speed difference between the two wheels, biasing torque to the wheel with more grip instead of sending all power to the slipping wheel. 
• Best for: Performance driving, track use, and slippery conditions. 
• Advantages:
  • Improves traction during acceleration and cornering. 
  • Makes drifting possible and easier to control. 
  • Helps prevent one wheel from spinning uselessly on low-traction surfaces. 
  • Can reduce understeer in front-wheel drive cars. 
• Disadvantages:
  • More complex and expensive. 
  • Some types may cause a slight "grab" in tight turns or under deceleration. 

Open Differential

• How it works: It allows the wheels to spin at different speeds, sending power to the wheel with the least amount of traction. 
• Best for: Everyday driving. 
• Advantages:
  • Simple, reliable, and inexpensive. 
  • Smooth and predictable handling in normal road conditions. 
  • No "grabbing" or binding in tight turns. 
• Disadvantages:
  • If one wheel loses traction (e.g., on ice or during hard cornering), it will send all power to that wheel and the vehicle will lose acceleration. 
  • Makes drifting very difficult. 
  • Less effective in slippery conditions and high-performance situations. 

What are the symptoms of a bad limited slip differential?

You can tell a limited slip differential (LSD) is bad by symptoms like noises, such as grinding, whining, or howling, especially when turning or accelerating. Other signs include shuddering or vibration, difficulty steering, excessive tire wear, and visible oil leaks from the differential housing. 
Audible and tactile symptoms 

• Noises: Listen for unusual sounds like grinding, humming, whirring, howling, or clunking, particularly when turning or accelerating. 
• Vibrations: Noticeable vibrations or shaking, especially while accelerating or cornering, can indicate worn internal components. 
• Shuddering: A jerky or shuddering sensation when turning or accelerating from a stop is a classic sign of worn clutch packs in the LSD. 
• Difficulty steering: The vehicle may pull to one side, feel "loose" in corners, or feel sluggish when turning. 

Visual and physical symptoms

• Oil leaks: Check for any signs of fluid leaking from the differential housing or seals. 
• Tire wear: Excessive or uneven tire wear, especially on the inner or outer edges, can be caused by the differential not functioning correctly. 
• Overheating: A burning smell can indicate that the lubricant is breaking down from excessive heat, which can be caused by worn parts. 

What to do

• If you experience any of these symptoms, have a professional mechanic inspect the differential, as driving with a faulty one can cause further damage and safety issues. 
• For a worn clutch-based LSD, a technician may perform a more specific test or recommend replacing the clutches or the entire carrier assembly, notes this YouTube video.