New 09 GT owner

Recently purchased from another Ed, former coworker, who bought it new & put 154K on it, and who just replaced it with a red 2017 SS.
I drove it when it had 150K less on it (ie right after he got it), and thought it was 'milder' than my 04 GTO re noise & ride, my general impression maybe putting a mile on it back in 09. Never thought I'd end up with it 14 yrs later.
He's really picky, so well taken care of. Looks very good for being as old & as driven as it is.

put 55 mi on it, driving it from his place to ours, to the store & Carl's Jr last Fri (cheesesteak breakfast burrito, yum) and today around the block (also because street sweeping here) Have yet to figure out how to set clock, or get familiar w/how radio works, etc etc. Will sit down with owners manual later tonight.

Plan is to drive to Yellowstone, via other National Parks in Utah, in a couple months as will be more comfy than the GTO.
So... before we go, things to check on? Don't think he's ever had any major mechanical repairs done that I know of.