2012 low on power

Truck recently doesn't seem to have as much power. No engine light or other symptoms, just doesn't seem to have as much power on acceleration as before. When accelerating feels like towing a heavy trailer or breaks on slightly. Only has 43000 miles. I cleaned the MAF and checked vacuum to see if signs of bad catalytic converter. Also seems worst if truck driven for more than an hour.

Trans?

Emergency brake stuck on a bit? Caliper sticking? Take a temperature reading of each wheel after driving for ten minutes without heavy braking .