What kind of oil goes in the transfer case a 1977 ford 4x4?

The recommended oil for a 1977 Ford 4x4 transfer case depends on the *specific* transfer case type. Ford used several different transfer cases in their trucks during that year. There's no single answer.

To determine the correct oil, you need to:

1. Identify your transfer case: Look for a tag or casting number on the transfer case itself. This number will allow you to look up the correct specification in a repair manual (Haynes or Chilton manuals are good resources) or online parts database.

2. Check your owner's manual (if you have it): This will list the recommended lubricant.

Once you know the transfer case type, you'll find the correct oil viscosity (e.g., 80W-90, 75W-90) and type (e.g., GL-3, GL-4, GL-5). Using the incorrect oil can damage your transfer case. Don't guess; find the correct specification.