I have an 05 Griz 660. The left front wheel has a lot of deflection. I assume it's the bearing as I have a big wheel kit on it and we all know those big tires are hard on the equipment. Anyway, I can't get the main bearing bolt loose. The service manual shows this as a sloted nut with a cotter pin. (similiar to what you would see on a car) My machine has a nut with a tall shoulder that has been bent in to prevent it from backing off. Regardless the nut won't come loose. I have tried a torch, impact wrench, breaker bar, penetrating oil etc.. Am I missing something?