Keep combustion pressure sealed where the head meets the block with the APEX Cylinder Head Gasket AHG551, a Nissan Altima head gasket also listed for the Nissan Sentra. It is a direct-fit replacement for the 2002-2006 Nissan Altima and the 2002-2006 Nissan Sentra with the L4-2.5L engine.
A head gasket sits between the cylinder head and the engine block. It seals the combustion chambers and helps keep the coolant and oil passages separate. Both L4-2.5L applications share this gasket, which seals a 2006 Nissan Altima cylinder head to its block the same way it does on the listed Nissan Sentra.
- Part type: Cylinder head gasket, APEX part number AHG551.
- Engine: L4-2.5L.
- Applications: 2002-2006 Nissan Altima and 2002-2006 Nissan Sentra.
- Quantity: The listed applications use one head gasket per vehicle.
Signs this part may need replacing: unexplained coolant loss, white exhaust smoke, overheating, milky oil or low compression. Other faults can cause the same symptoms, so diagnose the engine first. If a failed head gasket is the cause, AHG551 replaces it.
Replacing a head gasket requires removing the cylinder head. Consult the vehicle service information for surface preparation, the torque sequence, the correct head bolts and whether they may be reused.
