If older trucks are so great, then why are they for sale to begin with? If a truck has 100,000 to 150,000 miles, are they really still that good? Folks selling trucks every couple years, well ... those vehicles will NOT be in the OP's price range.
They say diesel can run 300,000 plus miles. I believe that. But... what about the body, the rest of the truck!
I've had 4 pick-up trucks in my lifetime. All thee were good trucks. My first was a Chevy S-10. The second was a gas 3500 dully Chevy Silverado, the third a 3500 diesel Chevy Silverado, and the 4th a diesel Chevy Silverado.
The S-10 was literally driving in the ground. The engine literally blew up in the middle of an intersection. But the doors were rusted out so bad, you could see the window mechanism from the outside of the truck. Not to mention the rust every where else.
My first gas 3500 dully literally, the frame rusted out. Transmission, engine, wonderful! Strong as an ox. But we sold it for about $8,000 at a dealer for another used, 2 year old diesel dully that someone drove on a 2 year lease. NICE truck and price was good, but way more than the OP's total budget amount
This one was a powerful work horse. We loved that truck. Put a lot of miles on it, towed wonderful, and there again ... strong as an ox. But, the fat fenders were made of fiberglass, and they had spider cracks in them, and were concerned about the fender just falling off in chunks some day. So, while the truck still had a somewhat, good appears, we traded for our current one. For what it's worth, dealer gave us $18,000 for a 9 years old truck. They patched up the fenders and hid the spider cracks, cleaned it up and turned around and put it back on their lot for $25,000. It had about 135,000 miles on it. (I kept checking their web side, and occasionally drove through their lot to look at the old gal, that's why I knew the repairs and cost). The one day, the truck disappeared.
What I'm saying is, a truck for sale in the $10,000 range, "might" have more much more life in the transmission and engine, but what about the body, the rest of the parts, rusting frame, suspension, and everything else. If older trucks were so great, wouldn't the original owners still own them? Bottom line, they are for sale, or sold to a dealer for a reason.
Yes, the OP may be able to find something in his price range, but "what" is he getting?
Now for all of you that have older vehicles and you're the original owner, "coodos to you!" Wonderful! Hang on to that truck! I'm not talking about you or your truck. But remember, YOUR tuck is not the one "for sale" out there! Someone else's reject is.
Just because a truck is under $10,000 does not mean its still a solid truck. Anything more than 10 years old ... watch out for the rust!