Why do I want diesel?
My next million miles. I am a roadrunner. I go places. I need something that will last me to my last breath. I want to buy the last truck I will ever need. I put alot of miles on my vehicles. I am 41, and I don’t know how many years this body has, but I want my truck to last as long.
Got it?
“I want to buy the last truck I will ever need.” “I am 41”
That’s rather naive. Name a single truck that is still running 40 years later that isn’t a rebuilt classic. Extremely few. Wow, you are just sooooooo old. *sarcarsm*
If you really want a pickup that will outlast you, find yourself an good condition 1970 ford F250 2wd with a 300six and a stickshift. If they don’t rust, they don’t die. Ever.
Ask a question and get a book
I could understand if you drive maybe 100 miles per year. Such a vehicle, if properly garaged and cared for, can last 40 years.
However, by your own admission, you are driving a lot. Sure, you can buy a vehicle that will last 4 million miles and 40 years, but it will cost far more than several different vehicles, all bought new, that last only 400K miles and are driven for 4 years each. The cost of a super-reliable truck rises exponentially, not linearly. But the cost of a number of disposable vehicles rises linearly. Since no vehicle in existence can last 40 years without maintenance, you need to include cost of that maintenance into calculations. You may need to buy spare parts because they will be out of production within ten or twenty years. This won't be cheap.
There are also other problems with buying a vehicle "for the rest of your life." There is always a possibility of a major problem that is not worth fixing. Something expensive fails; someone hits your vehicle, or you do it. Flood, fire, lightning, bad tires, bad fuel, bad road, corrosion - there are millions of reasons why a perfectly good car may become not so perfectly good. Cars are outdoors animals, they live in a hostile environment. Overpaying for "your precious" does not make much sense. Owning workhorses, one after another, is more practical.
Finally, do you want to drive a 30-40 years old, beaten up truck when you are older and hopefully more wealthy? Chances are that you will dump the vehicle as soon as you can get a better one. In 30 years I expect all vehicles on the road to be driving themselves. Your truck may be not even street legal anymore, not without a very expensive upgrade. (If your truck didn't come with servos for steering and brakes then it will cost a fortune to put them in.) Maybe even hydrocarbon fuels will be illegal by then, and everyone will be driving on electric power made by a pocket-sized fusion reactor. You are talking about a distant future.