It's probably normal, but here is a test you can do if you (or someone you know) has a scan tool which can give 'real-time' computer readings:
Test 1: Plug scanner in. Read engine coolant temp when the truck is cold, not started (like in the morning). The engine temp should match ambient outside air temp. Or be real close.
Test 2: When the truck is up to operating temperature, read the computer's coolant temp via the scan tool. Verify actual engine coolant temp with an infra-red temp gun pointed at the metal part where the upper radiator hose is...on the engine (the metal part ..not the rubber hose). That's where your coolant leaves the engine ...to the radiator. Bear in mind not all IR temp guns may be calibrated the same, so a couple deg difference will be ok.
Test 3: Also read/verify the outdoor temperature sensor reading.
If the temperatures you get from the tests above are off quite a bit, then the temperature sensor could be faulty, which would likely affect your truck's air/fuel mixture, esp during extreme hot and cold temps. Normally, if they are off a fair amount the engine might also 'miss' or stumble too, which you aren't seeing. Also check out the MAF reading too. There are some videos how to verify engine and outdoor engine temps.
Also, might be worth removing the engine rubber air tube (snorkel) from the air filter, inspect the throttle blade and surrounding area for fuel deposit build-ups. It only takes a very small amount to affect idle conditions, which can suck more fuel during idle. It's a normal maintenance procedure. Clean with a throttle-body cleaner (spray) and a solvent-safe plastic brush.