Fuel High-Pressure Union Nut Socket (T40055) — VW/Audi TDI Common Rail

Break loose or torque down the high-pressure fuel line union nut without rounding it. This socket is equivalent to OEM T40055 and sized for the union nut connection on common rail systems.

Why you need it

High-pressure fuel lines are tightened to a precise torque, and a standard wrench can round the nut or slip. A dedicated socket grips it fully.

Fits

• VW and Audi 4, 6 and 8-cylinder common rail TDI engines

Good to know

• Equivalent to OEM T40055.
• Confirm your engine code before ordering. Send us your VIN if you are unsure.
• Relieve fuel pressure before opening high-pressure lines.