I'm replying basically to explain why I didn't reply
Since you're new, I don't want you to feel discouraged or ignored though. But.... in a way it's like saying "I'm going on vacation what should I pack?" The answers could range from "waterproof matches" to "a tuxedo" depending on where you're going, what you plan to do, how far away you'll be from supplies, etc.
I'm sure there are jillions of lists online. Maybe not Chinook specific, but still good for ideas. As far as how to keep things quite/safe when you're driving: Boating forums will give you good ideas. I just can't stand things knocking around. I use old (clean) socks to put around some things, and also keep a bunch of "scoot guard" type stuff on hand (started with a roll; now have a bunch of pieces that I've cut). Also some things can be placed between layers of clothing, you can use towels you are already bringing, spare paper towel rolls, etc. for padding.
Barring any extremely specific mission (such as "I'm going to the desert and will be off grid in extreme heat and dust for 14 days"), I'd say pack lighter than you think you need to, and remember that there are stores along the way in most places you can take a Chinook. I'm not a big Wal-Mart fan, but just as an example, they are everywhere, often open 24 hours, have a reasonable RV supply section, plus clothing, food, bedding, motor oil, etc.. And you can often park overnight to boot.
There are also laundromats.
Reason I'm suggesting packing light is that a Chinook is not a huge space, and for myself, I DETEST having to paw through over-stuffed lockers and bins just to find something (and then getting home and realizing I wore the same two sets of clothes anyway...). Or having things that "permanently" live in the few open spaces that do exist (now there's a constant battle). That's not to say don't bring the basics, and since garbage and waste can be issues, I do bring "real" dishes and that sort of thing (vs. paper/plastic).
I'd also bring basic tools and tested equipment in case of a flat or roadside stop (reflective triangles, wrenches, etc.). Plus duct tape, zip ties, coveralls, and that sort of thing. A credit card and road service can come in handy. Plus of course have things reasonably well sorted out before setting out (fresh oil change if it's a long trip, good tires, etc.) But this has a HUGE range of personal choice, from people who just bring a credit card, to others who have spare fuel pumps, pre-packed spare bearings, two spares, and you-name-it. So there's no one answer.
As a general rule, I tend to prefer having dedicated things that I keep in a camper vs. having to haul "home" things in and out each time - but that's just one way of doing it.
Funny, but I found myself getting that "oh he's going on a road trip!" excitement for you just writing this, then realized, but wait, I'm already out in my Chinook now
BG
PS: On the subject of food: Depending on where you are going (and where you start from), you may find that smaller towns have more basic grocery stores -- or even only convenience stores. So if you're starting out in a place with a bigger selection, and there are certain things you really like (especially if they are little treats/non-perishable/hard to find) you may want to stock up a bit. The basics can be found pretty much anywhere though.