Turf Trac is one of those odd balls. It is not a relabeled MTD or Murray like a lot of unique names. I did own one(front engine tractor model). I believe they only made them in the 80's early 90's. There isn't very much info at all on them. What do you need to know?
If it has the 3 inch visible brake disc you need to adjust the retaining bolt for the brakes just right. Most riders also have an adjustment nut on the linkage that pulls on the brake spring tighter or looser. Just look and it is a pretty basic system.