Transmission & xDrive

Active M Differential

Varies rear-axle differential locking to help manage drive torque.

Drag to turn it Open in the 3D lab
Where it sits

In the rear differential on equipped BMW M models.

How it works

Electronic control commands locking based on vehicle and driver inputs rather than a permanently fixed lock.

Think of it as

A smart power-sharing gate between the rear wheels.

Symptoms when it fails

Warnings or traction changes can involve sensors, control or the differential assembly.

Lifespan

Use the exact gearbox and axle service guidance. Loads, seals, lubricant condition and driving use influence wear.

Repair cost

An accessible mount or seal differs from internal transmission work. Gearbox identification and diagnosis are essential to a useful quote.

The BMW angle

BMW’s Active M Differential uses vehicle signals such as wheel speed and yaw to inform control.

Used in

Equipped BMW M models; the F10 M5 manufacturer description is one documented example. Other axle differentials work differently.

Sources
Same system

Transmission & xDrive