Differential Gearing Types: Open Differentials vs. LSD and Lockers

The differential distributes power from the driveshaft to the wheels, allowing them to rotate at different speeds when cornering. The type of differential you choose impacts traction and handling.

Open Differentials vs. Limited-Slip (LSD)

An open differential is the most common type. It distributes torque equally to both wheels, but if one wheel loses traction (e.g., on ice), it will spin freely while the wheel with traction receives no power. A Limited-Slip Differential (LSD) detects this speed difference and transfers torque to the wheel with traction, improving performance in wet or slippery conditions.

Locking Differentials

Locking differentials (or lockers) lock both axle shafts together, forcing both wheels to rotate at the exact same speed regardless of traction. This is ideal for off-road use, but can cause tire scrubbing and handling issues on dry pavement. Calculate your wheel speeds and axle ratios using our RPM calculator.

Understanding Transmission Slip and Mechanical Power Bands

Accurate RPM calculations assume direct mechanical links within the drivetrain. However, real-world variables like transmission slip and torque converter lockup can cause minor variances. Automatic gearboxes feature torque converters that slip slightly under load, resulting in a higher actual RPM than the theoretical formula suggests. Manual gearboxes maintain direct contact, ensuring that calculations match physical speeds.

Operating your engine within its optimal power band balances performance and longevity. Running the engine at low RPMs under heavy loads can cause engine lugging, which strains mechanical bearings. High-rpm operations generate excessive heat and friction, necessitating quality synthetic lubricants to protect components from wear.