i would say find room for 10 gal. of fuel for a "safety net" especially if you are going to be exploring back roads. you can strap those down on a roof rack or the cargo deal above the spare.. sounds like a fun trip though. just remember, for LCOG you will want to store the heavier items inside the rig, and put sleeping bags, duffel bags, sleeping pads in the cargo basket(s) only reason i say put the fuel up there is to keep it outside of the cab, fumes will get to you after a few miles
the best thing you can do before a trip, is to just go over your rig very well, if you dont know when the fluid has been changed last you should probably do it, including diffs, tranny, motor, power steering, brake fluid, flush out all the systems and put new fluid in. check your brakes, check all your bushings, ball joints, tie rod ends, u-joints etc. its the little things that break on a trip generally. in my experience at least.. i would just do a complete tune up, spark plugs, wires, cap and rotor, clean throttle body, seafoam, when you do the oil change throw in some engine restore from auto zone, comes in a silver can with a soda style pop top, 4/6/and 8 cyl cans, i used it in my XJ's 4.0 and it made everything run ALOT smoother, only thing is, it eats up sludge so if you have a slow leak from say your rear main, or oil pan gasket it might start to leak a bit faster... change out the air filter, if you go insane like me you can index your spark plugs, which is basically, you buy an indexing kit from summit, they are little washers you put on the spark plugs, come in different thickness' each thickness determines where the plug ends up pointing, your goal is to get it to point just off center towards the exhaust side i believe, helps promote better detonation and directs the blast so it flows out of the exhaust port more efficiently (in theory) IMO anything helps... but then again like i said i am insane when it comes to this stuff, to the point where i will be pulling my head/intake and header soon to port match and polish the head/intake... anyways, i'm just rambling now, moral of this rant is, do a good tune up and your rig will love you! my xj is at 325,000 miles, all original drive train, if that isnt proof enough then idk what is...
