Following the first wheel, which wheel is bled second in the diagonally split system when replacing the left front caliper?

• A. Right Rear
• B. Right Front
• C. Left Front
• D. Left Rear

Answer: (C)

In a diagonally split braking system, opposite wheels share the same hydraulic circuit to keep braking available if one circuit fails. When you replace the left front caliper, that caliper is in the circuit that also powers the right rear wheel. The correct bleeding approach is to purge air from that circuit first by bleeding the opposite wheel in the same circuit—the right rear—before finishing with the replaced caliper. Once that circuit is cleared, the next step is to bleed the left front caliper itself to remove any air from the new line. That’s why the left front wheel is the second to be bled in this scenario. The other pair (right front and left rear) belongs to the other circuit and is addressed after completing bleeding in the first circuit.