Is Transfer Case Fluid Just Automatic Transmission Fluid? Ask Your Selden Mechanic

The correct lubricant for your vehicle’s transfer case is whatever the manufacturer has specified. Using anything that doesn’t meet their specification could increase heat, wear, and the risk of a failed transfer case.

• Some modern light-duty 4WD automatic and chain-driven transfer cases are designed to use a standard automatic transmission fluid.
• Manual and gear-drive transfer cases require thicker oil for better protection and higher loads. The oil is typically around 75W-90 or 80W-90.
• If you have your vehicle’s owner’s manual, it will specifically state the type of fluid that your transfer case is designed to work with.

A lot of vehicle owners don’t have their original manuals, so if you don’t have yours, you don’t need to worry. When you visit an auto shop for AWD/4WD service, an auto technician will check an extensive database to confirm the OEM recommendation for proper lubrication.

• A technician will check the oil in your transfer case for any gritty texture or contaminants that might suggest internal component wear.
• The system is fully flushed to remove the old fluid and contaminants.
• If you have experienced issues like hesitation, difficulty getting into gear, whining, or whirring, the system might be checked for damage and excessive wear.
• If everything’s in good condition, the transfer case will be refilled with a premium lubricant that matches the OEM spec.
• The technician will run the engine and idle it for a few minutes before verifying that the fill level is adequate.