I'm gonna kinda play devils advocate here a little bit... While I agree you don't need some "high-zoot" Expo rig for a lot of trips (and admittedly, a LOT of folks build these rigs and then drive on tarmac 99% of the time and camp in "full service" camp-grounds that they could have taken an RV to), it really depends on WHAT your goals are for a said trip. If you;re going to X set destination with set stopping points in between all on the highway then yeah, you can fairy easily predict exactly what you'll need and only take that or adjust your vehicle to better suit on road driving. BUT, if you plan on the road less traveled (in my mind that's the only reason to drive to S.America) then it pays to be prepared. In my mind (and admittedly I'm "that guy" and I love tools and stuff) it's better to "have and not need then need and not have". It all comes down to realistic planning and doing your homework. You can certainly drive a bone stock FJ62 down to SA, I mean it's not like everyone n SA has some fully kitted out truck just to drive around (although in some places they do... for a reason), but when you're relying on your vehicle the way you do on these long trips, it pays to be prepared... I'm in NO WAY trying to convince you that you need to build your truck up to some show-truck like level, just advising that you maybe go a few steps beyond "just in case". Might save you from the wife and kids hopping a flight home ahead of schedule and you coming home to an empty house aye
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The Chainsaw is a really good example. Have I used it on every trip I've been on??? No, not even close, BUT the times I HAVE used it, it's been the difference between getting to my destination and spending days clearing trees out of my path. SO, I take it with me most time I think I'm going to me in a place where I might need it. Things like that.
Also, you own an FJ62... if it's in good working order it's ALREADY an "expo truck" of sorts and really it'll take you most anywhere you want to go short of following the trail of the Camel trophy aye. It's a Toyota 4wd, they were born to do this kind of stuff and there are few things on the earth more idealy suited to this kind of trip then a Toyota Truck.
I will say though that I see some of these "overpacking" nightmares arise when people think they're "adventurous" but can't seem to camp without making it as close to the Four Seasons as possible. You;re taking a long trip and camping out of the truck. It's still camping so treat it as such. If you want to "take a break" you can always budget for a hotel room here and there aye.
Sorry if I sound like I'm talking down to you, I really don't mean to sound that way, I'm just showing the other side of the coin. It seems like some folks (not here typically, but on a lot of other sites like Yotatech and others) REALLY love to "poo-poo" fully built rigs as if doing it in a jalopy is some sort of badge of honor... That was ok when I was 19, but over the years (and many rafting trips with a "jalopy" set-up/gear) I've learned that the truth lies somewhere in between and over the years I've learned what works and what doesn't. It's not black and white, but shades of grey.
Most important of all... if you've got the "kit" you need to know how to use it. I've found folks on some of he "connecting trails" here in the NW that go from Major Highways to small towns on forest service roads/trails stuck because although they HAD a very nice winch and all the things that one would need to get unstuck... they had never bothered to learn how to use it. This may seem like a silly thing to suggest, but I advise that anything you buy for the trip you take out on a fairly "close to home" camping trip and USE IT. It's those little trips and fully using equipment that lead to the kind of learning that makes traveling on the long haul that much easier. Before we drove up to see my family in AK, we went out four weekends in a row to test out our packing/sleeping area set-up and by the 2nd week I had changed a LOT of stuff cause while it looked cool and seemed like a neat idea on paper, it didn't work or it was a PITA when you're having to live in the truck and do X task day in and day out. An example of mine was Jerry cans... I love them, I think they have MANY uses and carrying extra fuel is always good if you're not sure of your route of the conditions (esp. in a 4wd that might see a lot of low-range "work") they can be a PITA to get down and use depending on how your rigs set up AND unless they're in good condition and/or designed to be on top of your truck, mounting them can be a pain too. So, what I did is I went out and found two 10gal BOAT fuel tanks that had caps for "water tight" storage and put those up on top of the truck and I got a a long accordion pump "siphon hose" so that I could fill the tank without having to take the tanks off the top of the truck at all. They also have baffles in them to keep "sloshing" down to a minimum and really, not having to lug 10gal of fuel off the roof is NEVER a bad thing and they're low profile so they;re not a huge drag on the truck making mileage suffer even more. I may go to a Jerry-can mount on the back of my new bumper for the project truck, but I really do love being able to just climb up, stick the hose in the boat tank and then just stand there and "pump" my own gas into the tank when need be. It's a VERY fast way to refuel when the need arises. IF you do just go with standard Jerry cans, I highly suggest getting a mounting bracket/carrying frame for them to make mounting them easier and more secure. I've seen guys that think "hey, I've got a Jerry can, I'm set" and then they strap it to their roof with a single ratchet strap to the factory roof bars only to have it fly off the roof, break the factory bars, nearly injure other drivers and ends up wasting their spare fuel all over the road... No bueno.
In reality the point is to get out the door and go, but with some careful planning, realistic goal setting and evaluation of your needs/wants, you'll have an easier time of getting there and less chance of any "scary" moments (and this is more for your wife and kids safety... as well as the safety of your marriage :sombrero: ) that could put a damper on your fun aye. Also helps to be sure that your "traveling partners" know what to expect... Nothing can ruin a trip faster then having someone with you that's expecting to sleep in a bed every night and finds out that you're in the dirt 99% of the time aye
Enjoy the trip mate, I hope we see a "were leaving" trip report on here some day.
Cheers
Dave