What is the recommended differential fluid for the 2009 Tacoma?

The recommended differential oil on Your 2009 Toyota Tacoma is Toyota Genuine Differential Gear Oil LT 75W-85 GL-5. One of the products that You can use is Red Line Synthetic Gear Oil 75W-85. If You want to know the front oil capacity on the 4WD then it is 1.5L. For the rear, the capacity iS3.66 US quarts for 2WD vehicles. For 4WD vehicles, the capacity iS3.12 US quarts. The main purpose of the differential fluid on Your Tacoma is to keep Your differential lubricated. Without the fluid, You will risk Your differential becoming overheated and possibly ruin or risk ruining its metal components. Make sure You are checking the levels at least once a week to avoid that risk.