Old cars/trucks in my experience are very reliable. I own a 97 newest thing i have and also has been the most $$$ for repairs compared to my 80's and 70's cars/trucks. My wife has a 2002 truck that has left her on the side of the road 3 times. I have an 86 ss monte carlo that i know i've not spent over a $1000 since i've had it on repairs. I bought it when i was 17 and now 29 the 305 doesn't use a drop of oil with working on 200,000 miles on it.
The point i wanted to make is below
The previous owners has alot to do with it to most of my stuff was well taken care of ALSO the "new" replacement parts you buy now aren't always the best quality out there anymore (overseas) i always try to buy the best i can.