What's The Differences For The Car Now And The Car Then?

There are some major differences today from old manufacture cars.
  1) body frame.
  2) computer control.
  3) maintenance paradigm.

  1) the car body was fastened to a rigid, structurally independent FRAME (like hanging ornaments on a christmas tree).  This technique may still be in use, but most passenger vehicles are constructed with "unibody" techniques.  Some of the car body provides the structural strength instead of a frame.
  2) microprocessors monitor and control many more functions, both engine and other systems as well.  Mostly this is a good deal for the vehicle owner.  For less than a 100 bucks you can get an OBD Scanner that let's your car's computer "talk to you".  If you do this before taking your car into the repair shop you might then have a better idea if the shop is telling you the truth about what needs to be fixed.
  3) I can tell you from personal experience that engines are designed and the engine compartment laid out on the assumption that the car will be placed upon a hydraulic lift to get it up into the air so u can walk under it!  In some cases, owner maintenance is a thing of the past.

Another difference in cars from the past and present is the tune up. I remember I would need to get a tune up every other year. Nowadays, a car can go up to 100,000 without getting a tune up.