What is a differential lock?

Forces both wheels to turn together. A differential lets wheels turn at different speeds — great for corners, but if one wheel is in the air it spins and the car gets stuck. A diff lock connects both sides together, so the wheel with grip keeps pushing.

Try Diff-Lock Mud Truck for free

Gearbox & Drivetrain Cars booklet pack: 30 PDF booklets for $5.99. Instructions only; individual booklets remain free.

Explore the printable pack

Try it yourself

Lift one wheel off the table and try to drive, with the lock off and then on.

Build it: the build that teach differential lock

  • 🔒 Diff-Lock Mud Truck: Stuck in the mud? Slide the diff lock and both wheels are forced to turn together! (level 4 of 5, about 60 minutes, 33 steps)

In the classroom

Common engineering questions

How can I try differential lock at home?

Lift one wheel off the table and try to drive, with the lock off and then on.

Which builds teach differential lock?

One MightyCog build teaches it: Diff-Lock Mud Truck. Start with Diff-Lock Mud Truck: 33 steps, about 60 minutes.

Ideas that go with it