IDK, Its been a while since I used a larger Exmark. But if your trying to cut 8" of wet thick grass down to 3", thats might be the problem right there. Today was the first real day for mowing for us and we were cutting down serious cabbage at a few places, had to double cut most places. But the Gravely's cut right through it but our decks are set at 4" right now. No mowhawks or trails of any kind just a lot of soupy green mush. If I remember right, we used to have an Exmark Viking and it would leave a row of uncut grass when it was thick and tall.