I read through all the previous posts, and I can't help but think that I never realized I wasn't the only one.
My daily is a 97 k1500 5.7 Burb.
In my somewhat reckless youth I drove a wide variety of vehicles from opposite ends of the earth, on a regular basis, and because of naive youth was never adequately prepared. After a couple of movie level close calls, including one involving walking out a forest road in Central Idaho mountains in November, with tennis shoes, a light jacket, no hat, no gloves.
I can tell all in perfect levity, that I had a lot of time to talk to myself that very long night while walking. I came to decide/ promise myself that night several things:
1) adventure without planning is reckless, and may cost a life, yours or others.
2) however warm you think you are in a vehicle, you Will be cold once you leave.
3) carrying supplies and never used will never be a waste.
My winter bibs, coat, gloves, hat and boots only belong in 1 of 3 places. Wearing them, stored under the seat, or being washed. December, may, August, no expectations. And I haven't been cold in over 20 years. Food, money and EDC stuff in the pockets are extra.
The kit has grown/evolved to amass:
Tool box with basic maintenence and repair tools.
Spare coil and ecm already mounted to a factory bracket.
Spare belt, 6 ft of 3/4,5/8, and 5/16 fuel line
Cap, rotor, wires, plugs. Everytime I replace I test the new set. ( 100-500 miles)
Electric wire, safety wire, etc.
The coveralls, full set of clothes, tyvek, cheap tarp and cardboard are part of the kit.
These are on top of the fluids I carry either under the hood in a factory carry box (oils), or along the passenger side of the rear water and antifreeze ( i carry full strength AF, and water cause i can drink half of what I carry, if it was 50/50 I couldn't drink any of it).
I have a 20# fire extinguisher, and I have used it twice over the years ( never on my vehicle)
Just for giggles, I once weighed all the stuff I carry ( uI had unloaded it all to replace the carpet and had it all sitting on a pallet.)
It weighed 180#, about the same as a passenger. So I figure it doesn't cost me any real mileage, just space.
I have still had things go wrong while traveling, but I'm much more prepared to deal with them. The last adventure happened year and 1/2 ago while driving through Tennessee in July. Ending up troubleshooting a broken wire at the edge of the connector for the ecm, lucky for me the connector is a stock item at any auto parts store in the country. Took me longer to walk to the parts place and back, than it did for the diagnosis and fix. Now guess what else I now carry on my spare parts box? Yep, insulated barrel connectors that I could use to make any temp connector and a couple of spare connectors for good measure.
Anyway, long post I know. Reading all these others make me realize how each of us have had life experiences and how what we carry reflects the level of risk we are willing to endure. This is the mark of earned not learned wisdom.