Ok, out of the blue 10 days ago our Roper dryer started acting up.
Load clothes, turn dial and push start button and it makes a wierd loud buzz and nothing happens.
I push the drum, slam the door and push the button and it may or may not work. Most of the time, NOT. It just makes the buzz sound and nothing happens.
So, over the weekend hubby and I take back apart, clean out lint, check start switch and timer switch. See nothing wierd, etc.
Put it back together and it works at first, then does it again.
Now, if it is left on a Timer section instead of Off, it buzzes. It barely works. Luckily yesterday I got it to work, with much finesse so I could dry several small loads. It has also started to buzz if door is closed and timer knob has dropped into a start section, like it may be loose because it never dropped before.
I say it is the TIMER switch that is going bad. Hubby says it is the STARTER switch. It is $60 for TIMER and $7 for STARTER online ordering, so that is a big deal.
Any ideas? I cannot afford a new dryer right now!!!
FYI: It is almost 5 years old.

Here are your parts
Replacement parts for WHIRLPOOL REX6634PQ0 | AppliancePartsPros.com

Here is the wiring diagram
https://www.servicematters.com/d...0Sheet%20-%208528187.pdf

Sounds like the motor is shot, try the below

Try turning the drum by hand. Should turn fairly easily.

This may take 2 people
Open the door
Manually hold the door switch closed
Push the start button and manually rotate the drum in the correct direction.You probably will not need this step as the motor is already trying to start.
Watch your knuckles in case it starts up.
If it does start up, odds are high that you need a new motor.

It also sounds like the start switch is now shorted and will have to be replaced. This could be caused by the motor pulling too much current and the switch's contacts have welded together. See the Note below for possibility #2.

As Sidfink43 said there is a possibility that it is only the start switch.
Perhaps the contacts are badly pitted and have a resistance. This will drop the voltage and the motor will get less voltage so may not start.
The way to check it is the same as the door switch. Unplug the unit, remove the wires from the switch, short them together, tape them up so they cannot short to anything else, plug the unit in and give it a try.

If it still just buzzes and the manual start above works then I would lean towards the motor being shot.

Note: Other than a wire shorted wire there is a another possible cause for the constant buzz and no start..
If the centrifugal switch (5M/6M) is held closed or it's contacts are welded together it will give the same symptoms as a shorted start switch. Also the motor will not start on it's own because it's start winding is not in circuit.
The way to check is unplug the unit, disconnect one side of the start switch, tape it up, plug it in and give it a try. If it still buzzes and manual start works then it is probably shot. Either the contacts are welded or the mechanism to activate the switch is broken, in either case you will need a new motor.