All of Chrylser's early engines, the Big blocks, the LAs (and Magnums), and the Slant 6 (to paraphrase the old Jeep commercial, the Slant 6 wrote the book on reliability) are as reliable as can be. No fancy materials (aluminum, plastic (sorry, composite) intake manifolds, etc.). Just solid cast iron, with many years of production and refinement to work out all of the bugs. Same goes for the 3 speed Torqueflites. Of course, some of the current materials are being driven, indirectly, by government mandate/regulation (emissions, fuel economy, safety), and some by customer demand, Also, both transmissions and engine families are much shorter lived than in the past (we don't get engine families lasting decades any more). The other point is that mechanics were mechanics, and the good ones could tune car by ear, or take it for a drive and pretty much know what was wrong with the car by the time they came back. Now, "technicians" read computer codes, and guess at what part needs to be changed. Not directly related to reliability, but the ease of working on pre-computer controlled cars, and the relatively inexpensive repairs allowed people to maintain them at a lower cost, which encouraged upkeep. Now, take a new car to a dealer, and you won't be getting out for much less than $1000. And this doesn't take into account that older cars could be maintained at home far more easily. Example from personal experience: I was talkng to a friend of min about my cars, and said that I needed to get to a lock smith to get spare keys made for my J bodies. He asked how much that was going to cost. I told him I wasn't sure, but probably somewhere around $5-7 each. He said a spare key for his Honda Civic was $100, plus $200 to the dealer to program the key into the security system so that the key could actually be used. $300, FOR ONE KEY. Any wonder he didn't get a spare key?
Kostas