Anybody know what causes a washing machine to just spin when it should be agitating?

It is a 5 yr old machine.  I took the  cover off and the belt seems ok.

Thanks

This might sound weird but no kidding.  There is a thrust bearing under the tub, where the pulley is mounted and if it grinds itself to death you will have that effect.  It cost under 20 bucks to fix mine.  I have a Maytag, which is a Kennmore and a Wards I believe.
The local parts guy was cool and told me how to do it, he would stop by for 30 bucks labor if I could not.  It was not too hard and took an hour for me to fix this.  Mine was about five years old at the time as well.

If you have a matching dryer, the teflon rollers for the tub are about to go as well,lol  good luck

gene...you are one amazing dude!!!

try gene's tip. i had the same problem on a kenmore.

Washers should last more than 4 or 5 years.  My Maytag just gave out after 22 years.  I replaced it with an 18 year old Hotpoint that I got for free.  Wost part was moving washers up and down basement stairs.  The Hotpoint has 2 cinder block counter weights in it and the Maytag wasn't any lighter.

Just this week, my parents replaced their 20yr old Maytag washer. Out of those 20yrs, they had to call the repair man only ONE time!!!

Recently our set (washer and dryer, aged 18yrs.) both went down. I told the bride of 27 years not to worry, I could fix. She said she would wash my clothes when I fixed them, so about a week later,I bought a new set.  I can fix nearly anything, but not them!!!! fullclip

In my opinion, washers and dryers should last a good deal longer than 5 years.  More on the order of 10+ years.  

While you are mucking around with the washer, replace the hoses with braided stainless ones (burst hoses are a bitch for flooding the house), and check the exhaust hose from the dryer.  If enough lint builds up in the exhaust, a fire can result.

If you are building or remodeling, a drain pan beneath the washer and water heater is a great idea.

Now dishwashers are a POS, and I'll replace our $300 Kenmore with a $700 Bosch, in hopes of getting more than 5 years from a dishwasher.  Ours went to hell in a hurry.

It's really hard to say what's wrong without knowing at least what brand of machine it is.  kind of like saying "my gun jams" - a little more info would be helpful.

But since you said "belt" then it may be a Maytag.  If that's the case, your transmission is locked up.  Maytags use a reversible motor to turn a self-contained transmission under the tub that agitates when turned clockwise (looking from the top) and locks solid when turned counter-clockwise for spin cycle.  The controller merely switches power leads to the motor to make it turn the correct direction.  The water pump also runs off the belt so it actually turns backwards during agitation and forward (draining the tub) during spin.

If the tub spins the same way during "agitate" as it does during "spin" then you have a controller/motor problem.  If it turns the opposite way, then it's the transmission.

And if it's not a Maytag, throw it away and buy one!!!  [:D]  Or at least give us more information to work from next time.