If it's 70's silver gear and each piece weighs more than 25 lbs, it's probably something worth much much more than you think. Sometimes this old stuff is literally worth it's weight.
Even much of the early 80's stuff, after they went black is great gear. The late to early 90's maybe not so much, all depends on the make/model. If it was top of the line (TOTL) at the time, it's usually a keeper or has some value. If it's BPC (Black Plastic Crap), it's probably Goodwill fodder.