Going through some of those parts, chances are some of them are probably unsealed - though I suspect google maps will always generally try to pick the sealed roads.

As for petrol stations... Yeah keep a few Jerrys with you, just in case, as well as a spare full size tire or two (space savers are a bad idea in the outback) as well as a toolbox, with basic tools, hose clamps, etc. and plenty of drinking water/snacks. Maybe even a few packed lunches.

The nullaboar (Latin for "no tree") plains along the coast of south/western Australia are well known for having the one long, straight, featureless Eyre highway with a whole lot of space Between petrol stations. The most dangerous thing about those roads is fatigue from looking at the constant unchanging scenery for hours at a time. The second is running out of fuel or breaking down - where you gotta hope you've got the shit to fix stuff, because it's highly unlikely you'll see a friend on the road for at least an hour or two, if not longer.

It's so long that there are three designated airstrips on the highway designed for emergency landings and air ambulances (royal flying doctor service FTW - seriously, those guys deserve all the praise, true heros)