list of tv episode from yrs of 1976 thru 1978?

Question

main characror eas two men and ond big dog. man age was mid 40s and other man was early 60yrs old.

Answer 1

If it wasn't for the ages and the years, I would have thought it might be "Simon & Simon", but A.J. and Rick weren't that old though Rick had a very large dog named Marlowe.
http://en.wikipedia.org/wiki/Simon_&_Simon

I'll keep sorting through my TV memories for a series that might match your description.