check to see if the height adjustment on the blade deck is the correct measurement. put the mower on a level surface, put the pin in the 5 inch hole and lower the deck. take a tape measure and measure from the ground and to the blade tip an see if it is 5 inches....i did that to mine and was off 3/4 inch and had to adjust it after checking air pressure in tires. tires do wear so i guess you will lose some inches. i noticed when cutting st. augustine grass, i set my deck at 5 inches cuz i think the tires sink alittle while mowing so actually i'm probably cutting at 4.5 or so. i have the turf tiger so its heavier then the cub. just an idea.:dancing:Im going to take it to the Scag dealer, this week. Just to see.
And maybe due to the size and weight it just doesnt agree with St. Aug!