Yep. the old school numbers have never let me down. First change at 60, then every 30 after that.
pay attention to make sure you get the right fluid type for the trans - probably valvoline ULV. In my 2018, a quarter bottle (very small dose) of “lubeguard red” made the difference between me selling and keeping the truck. If it’s awkward shifting from 3rd to 4th or 5th, go ahead and add it.
I used a mityvac to suck a few quarts out, then 6’ of nylon hose with a funnel stuck in it to fill it from the topside. Also, the dipstick (it’s a little stubby thing) from the 6 speed transmission fits and is useful as a before/after reference point.
you need a 19mm closed wrench to break the fill plug loose. the plug will gouge if you get crooked on it.