It feels like the tires are under inflated (they are not), or the parking brake is on (its not). I drove it today after it sat a few days, and it felt stronger. When I go down a hill at 60 mph, if I release the gas it slows down, while my other truck does not (and the 5.3 doesn't on a good day). So, what are a few things that I can do that aren't obvious to make it feel younger or peppier. Also, it has ~180,00k miles and has had great care taken (oil every 3500k, garaged, etc.).
Thanks

 

check the fuel fliter,air fliter maybe a spark plug loss maybe change ur oil to a thicker oil

 

Believe I'll check the fuel filter, the others ought to be good.
Thanks