[richappy]

A slow spin sometimes is due to dragging brake shoes if nothing stuck in the tub, or a broken filter under the spin basket.Shine a lite in the basket to check, or just remove spin basket.
I confirm by measuring the spin motor current. If well over 9 amps,with no water in tub, that confirms it. Another indication is a jerky, noisy stop at turn off. A really serious indication, is a smoking motor! To confirm further, remove pump and motor and turn tranny coupler clockwise till basket starts to turn, if very hard to turn, this confirms it. I just repaired one with a jerky stop and found it cracked the motor epoxy and ruined the motor bushings!
Be aware,dragging brake shoes will eventually ruin the motor bushings, smoke the motor run winding, and accelerate the wear out of the brake shoes,clutch, coupler and tranny nylon gear.
To replace brake shoes, first remove motor, pump, agitator and tranny. If the washer is more than 6 years old, you may find the tranny hard to pull out. You then will need to clean/scrape the spindle just above the spin tube seal to let the spindle slide out easily. You can do this when you pull out the tranny. Then, loosen the spin basket drive block nut, pound down on the loose nut and pull up on one side of the spin basket to break free. If you don't have the special spanner wrench, you can use a small pipe wrench and a heavy hammer, just turn it counterclockwise. It is recommended to use the special spanner wrench. You can order it by calling this site.
On the bottom of the spin tube, pry down the spin tube sufficiently to get the brake shoes clear of the brake housing. Do NOT pull the spin tube out all the way, it's not necessary and you will have a mess of turbine oil on the floor and it will require more work. Then remove c clips, spring,plastic cam, steel cam and brake shoes.
I have not checked recently, but I think the brake shoes are no longer available. Check the brake shoe cam rollers for excessive wear. If worn, I routinely grind down the shoe pads by 1/4 of total thickness. This will solve your problem.Also, replace the clutch if worn, part # 285785. If not worn down to the rivets, just add a small nut to one side of the spring retainer, just make sure the spring is still retained. Check the brake housing for rust pits, if so, I put oil on the brake shoe pads.
Oil the brake shoe cam rollers, Re-assemble, pushing the spin tube up all the way. Pack silicone grease in the upper spin tube seal before putting back the tranny. Now check motor current, should be lower than before. Before tightening the drive block nut, make sure the spin tube tabs are in the spin drive block slots. Just push down and turn the spin basket till they fall in place.
This repair is a lot easier and cheaper than replacing the entire spin tube assembly!
Note: Be careful not to grind too much pad off the shoes, if you do, it will take much longer to stop and make more noise. Also, you may need to tilt the washer back a lot more to keep the spin tube from sliding down. If it slides down, the brake spring might jam against the clutch housing.
Good luck

[IvelDesigns]

maybe it's just me, but this seems pretty complicated for a person who has never worked on a washing machine before. would you agree?

if i were to call a repairman, what kind of charge should i expect to pay?

**edit**
sorry, forgot to say that i am having an issue with spin only. agitate works, drains fine, but won't spin even with one wet towel in it. there is a burning smell if we leave it, however, if you help start it by hand, it will spin up to speed on it's own.

this is in a kenmore 90 series

[richappy]

Jamming brake shoes is your most probable problem. A servicer would replace the spin tube and charge about $200 or more depending on labor rates. Makes the repair more than it's value!!
It's worth a try, but you really need the special spanner wrench sold by this site as the Whirlpool drive block nut spanner wrench, don't know the part #. If you buy it, please inform this site the part # and cost.