Product review (5 stars): KENMORE 90 SERIES DRYER - MODEL 110.66902691
This repair kit fits a Kenmore 90 series Dryer, Model # 110.66902691  PROBLEM:  Dryer started to squeal (high pitch)...like a little piggy!

When I took apart dryer I noted the following:

ORIGINAL PART NUMBERS and their corresponding REPLACEMENT PART NUMBERS:
1) Dryer Idler Pulley > stamped on original pulley> FSP WM 697 691
 Replaced with P/N 279640 came with tri-ring retainer clip and flat washer
2) Dryer Drum Support Rollers (front green in color) > stamped on original roller > FSP GRN 3396801
 Replaced with P/N 8536974 came with (4) tri-ring retainer clips and (2) rear rollers
3) Dryer Drum Support Rollers (rear red in color) > stamped on original roller > FSP 8536973
 Replaced with P/N 8536974 came with (4) tri-ring retainer clips and (2) front rollers
4) Dryer Belt > stamped on original belt > 3387610 EB made in USA > (size 93.5, 1/4W, 4ribs, 3grooves)
 Replaced with 40111201 (size 93 3/8, 3/8W, 5ribs, 4 grooves)

This kit came with instructions and all parts needed to replace (4) support rollers, Idler pulley and belt.  GREAT PRICE TOO!  Did an extensive search, this was the best price!  Even if you only have to replace one drum support roller. The price for 1 drum support roller almost cost as much as this kit. Might as well replace all the support rollers, idler pulley and belt too!  In addition, Express Parts Direct shipped these parts to me in (3) days!

Go to online video Dryer Repair - Replacing the Multi Rib Belt (Whirpool Part # 661570) for instructions for dissembling your dryer (110.66902691)
Install takes about (1) hour start to finish, time is needed to vacuum out bottom of dryer once drum is removed.  Great time to grab the kids to help.  Had my 13 year old son follow in my footsteps, I did one side, he copied me and did other side.  Had him install the belt over the idler pulley too.

Great time to clean out the lint trap, vacuum the inside of unit, vacuum under the dryer and wipe down top panel, bottom panel and remove and clean all knobs.

My dryer runs like a charm and no more piggy squeals!  I am a mom, if I can do it, so can you, grab the kids so they can help too!

Hope this helps!  Behappy doing your next repair!!