Whirlpool Gas Dryer no heat, rattling, spinning

Whirlpool Gas Dryer Model # LGR8857EQ2. Dryer drum spins but there is no heat. On the very few occasions when it does give heat it’s only for a few seconds until a loud rattling/grinding/scraping noise begins. Heat then quits completely though the drum continues to spin and the noise continues intermittently. Heat ceases when noise begins and I assume that’s not simply a coincidence. I have the back off but have no idea what I’m looking for/at. Anybody with any ideas as to what may be causing the above symptoms? Thanks for the help.