NISSAN 31397-90X0A Automatic Transmission Oil Pan Gasket

The genuine NISSAN (SKU: 31397-90X0A) automatic transmission oil pan gasket is a premium OEM component essential for the proper, leak-free operation of the automatic transmission. This gasket ensures a precise seal between the transmission housing and the oil pan, preventing automatic transmission fluid (ATF) leaks and protecting the internal system from external contaminants.

Key Functions and Importance:

• Reliable Sealing: Prevents high-pressure and high-temperature transmission fluid from escaping the system.
• Hydraulic Pressure Retention: Automatic transmissions rely on hydraulic pressure; maintaining proper fluid pressure is critical for accurate and smooth gear shifts.
• Contaminant Exclusion: Keeps road dirt and moisture out of the transmission, protecting the valve body and friction plates from premature wear.

Technical Characteristics:

• Material: Specialized oil- and heat-resistant elastomer or reinforced composite engineered to withstand the chemical formulation of ATF and high operating temperatures.
• Installation Position: At the lower oil pan of the automatic transmission.
• Durability: Excellent conformity and resistance to aging, minimizing shrinkage or hardening over time.

Symptoms of Wear or Gasket Failure:

• Oil Spots Under the Vehicle: Reddish or brownish transmission fluid leaking onto parking surfaces.
• Low Fluid Level: Decreased ATF level due to leakage, leading to shifting irregularities.
• Slipping Gears: Inadequate hydraulic pressure causing delayed or hesitant gear engagement.
• Overheating: Elevated transmission operating temperatures caused by insufficient fluid volume and lubrication.

When performing a transmission fluid and filter service, replacing the oil pan gasket is always strongly recommended to ensure a dependable, leak-free seal.