I used to slap any old belt on a Whirlpool washer until a guy in Cleveland set me straight
For about 4 years I kept a few universal belts on the truck and just matched whatever was closest when a customer did not want to wait on a part. Last month I was doing a Kenmore 90 series in Parma and the guy watching me was a retired tech named Ray, and he asked why I was not measuring the groove angle. He pulled out a little gauge and said the wrong belt rides high, slips, and eats the pulley in about 6 months, and I had never once thought about that. I bought the gauge for $14 and now I match the exact part number even if it means a second trip. Anybody else keep a groove gauge on the truck or is that overkill for most calls?