Absolutely take the car - 2 hour trips should have worked out the kinks but just in case I suggest pretending you are on a rally and pack items that you may need. - zap straps, duct tape, bailing wire, crescent wrench, couple hose clamps, screwdriver with multi heads, nitrile gloves, spare spark plugs, spark plug wrench, antifreeze, tire gauge, flashlight, leather gloves (for heat), painters coveralls, extra fan belt, small tool kit, pliers to cut wire, jumper cables, ohm meter, circuit tester, fuses, brake fluid, bicycle pump, reflective cones, camera etc. This should all fit under the parcel shelf.
Check the archives - should be a list for rally gear.
I carry the above with me all the time because you never know when someone says let go to..... and you do it. Out here - in 10 minutes you are in wilderness so be a boy scout and be prepared to have fun.
Stop often to fill up so that you reduce the chance of getting crap gas. Everytime you stop check the oil and brake fluid and antifreeze and as you open the hood, take a wiff and smell the engine - pretty soon you can tell whats happening by smell - especially smell by the exhaust to make sure nothing is burning. - Don't forget to smell the wheels as go around the car. The last time I did a trip like this in an unknown car I removed the hubcaps and everytime I stopped I checked to see that the wheel bearings were not everheating as well (just carefully touch the middle of the wheel to see how hot it is) and a couple times I checked the wheel lugs for tightness.
Have fun - wish I was coming with you.