I service accounts with larger Cats, 9k-15.5k all running the powershift transmission 1 speeds. I couldnt ask for a better transmission, as they are holding up to pushing and pulling paper in a paper factory and wallboard mill. They use paper bale clamps with 1500lb bales of cardboard and drive around the plant balesweeping, or other words pushing loose pieces of cardboard into piles, and pushing sometimes up to 6 bales into a ramp (beater), 24-7, over 600 hours a month, keytroller states 80 starter starts per day, and had no failures until (only one) they hit 15k hours or one hit a pole head on, cracked tranny case in half.