Maytag dryer that make loud rumbling sounds. It takes forever to dry.

any ideas?

I Had This Happen Several Times To My Maytag Dryer. .i Took The Belt Off Of The Motor And The Motor Ran Noisey.. I Replaced The Motor.. I Found One On ********. For Less Than $100.00 A Appliance Parts Store Wanted Over $700.00 For A Motor..
Months Later It Did It Again But It Was Not The Same Noise It Did It When The Dryer Was Cold And Stopped As It Warmed Up..

I Again Removed The Belt To The Motor, And It Did Not Have Any Noise.. I Removed Power And I Turned The Motor By Hand And I Had A Noise When I Put A Side Load On The Motor Aft Pully..when I Installed The Belt Again.. The Dryer Made A Grinding Sound More In The Foreward Part Of The Dryer..

What I Finally Found Out.. Was The Fan Cage Was Broken At The Motor Shaft And When It Did Rotate, With The Motor, It Was Not Spinning In A Clean Rotation. It Was Spinning In A Egg Shape Or Wobble Rotation.. Hitting The Edges Of The Fan Enclosure Making The Grinding Or Rummble Sound..
You Need To Take Off Two Split Rings To Remove The Fan Blade Or Cage.,,i Had To Order Part Number 3-12913 Fan, On ******** For Less Than $10.00 A Parts Store Wanted Over $70.00 For The Fan, Or The Number Should Be Somewhere On The Old Fan Cage.
To Reinstall The Belt. .understand How It Goes Around The Drum And Around The Belt Rollers ...you Will Need To Pull On The Belt Tension Wheel Towards The Motor Until You Can Pop Or Install The Belt.. Turn The Drum A Few Times To See That The Belt Did Not Get Twisted..
When I Opened Up The Front Of My Dryer To Get To The Fan Cage.. I Did Find The Exhaust Was Filled With 30 Plus Years Of Lint Aft Of The Dryer Filter And The Fan Cage. Which Ment It Was Not Venting The Past The Fan To The Outside Of The Dryer..