To identify it, you'll need to:
1. Locate the fuse/relay box: This is typically a black plastic box under the hood, often near the battery. The exact location might vary slightly depending on the trim level and options. Consult your owner's manual for the precise location.
2. Consult your owner's manual or a wiring diagram: These will show you the location of the starter relay within the fuse/relay box. They'll often provide a diagram showing the fuse/relay positions and what each one controls. Online resources like repair manuals (some free, others paid) might also have diagrams.
3. Look for relays that are appropriately sized: The starter relay will be a fairly substantial relay compared to others in the box. It'll likely be a larger, heavier-duty relay.
4. Check the relay's function (with caution): If you're unsure, *do not attempt to test it with the ignition on*. Use a multimeter to check if there is power going in and out when you try to start the truck. *This should only be attempted if you're comfortable working with automotive electrical systems.* Incorrectly testing relays can damage your vehicle's electrical system.
In short, you won't find a standalone "starter relay" labeled as such. It's a relay within a larger fuse/relay center. Referencing your owner's manual and/or a wiring diagram is crucial for correct identification.