I am unsure of the age of the dryer, we just moved into our house 3 months ago and it’s the one they put in when we requested a dryer (It looks old).
Ok, the dryer had been working fine, then recently, when i’d push the start button, it would make a loud noise when starting up (the noise would go away right away, it was just when it started it make a noise). Well the other day i washed a comforter then dried it. When I went to restart the dryer (because it wasnt all the way dry) the dryer just made a loud buzzing (the noise it makes when the cycle is over, to tell you the cycle is over) and would not start, it didnt stop buzzing until i opened the door. I called the dryer repair people and they were scheduled to come out. Well the night before they were supposed to come out, I tried just for S&G to start it again, it started!!! 
I was happy! Cancelled the appointment and washed some clothes. The put them in the dryer and it worked, then my nightmare…i went to restart the dryer for a 2nd cycle…same loud buzzing! What could this be? I havnt tried it again today as i’ve been at work. I’m sure it will probably work again for one cycle. :(