However, generally, 5W-20 is the most common and likely recommended viscosity for a 2004 F-150 4.6L, *especially if you live in a moderate climate*. If you live in an area with extremely hot or cold temperatures, you may need to use a different viscosity, such as 5W-30 in very cold climates or 10W-30 in very hot climates.
Always check your owner's manual for the specific recommendations based on your operating conditions. The manual will provide the exact viscosity grades suitable for your vehicle. Using the wrong viscosity can harm your engine.
