Thanks, Howard the version my friend is looking at is a 4wd model.Turns on a dime, will try a dealer for a manual. By the way what is a ZTR version?
On a ZTR, the mowing deck is suspended from the frame of the machine and sits beneath the operator. The wheels that are in front of the mowing deck support the weight of the entire machine. Unlike a tractor, the engine is behind the operator.
An F mower is very much like a compact tractor with a rear finish mower on the 3 point hitch, but with the seat and steering wheel turned around facing the rear, and the discharge facing the side or the tractor. The wheels out in front of the mowing deck are anti-scalp wheels; they do not support the weight of the tractor. The front of the tractor is now the rear, and the rear is the front with the mower out in front of the operator.
An F series can turn more sharply than a small tractor, but a ZTR can do a 180 and leave no grass at all uncut. In tall grass, a ZTR can leave windrowing (the front weight bearing wheels can mash grass down flat before the mower gets to that point, preventing it from being cut-it may or may not pop back up later). On an F mower, it is possible to lift the deck (which is basically cantilevered out in front of the rest of the machine), allowing every blade of grass to be cut by a mower blade before a tire ever touches it. The lift mechanism is far more limited than a 3ph, however. Quick attach allows the mowing deck to be replaced by a number of other implements like sweepers, front blades, snowblowers, etc.
A ZTR is steered with twin joy sticks. Power is applied to the rear wheels independently. If you want to turn left, you push the right joy stick more than the left. This causes the right rear wheel to turn faster than the left and the greater push on the right side makes the unit turn left. You can even push the right lever forward and pull the left lever back, making one drive wheel turn forward and the other back. This causes the machine to pivot in place. This design is what allows the turn radius of zero.
The F series, being in essence a regular tractor driven in reverse, is steered by its rear wheels like a fork lift. As stated above, steering is with a steering wheel. This rear steering gives it a better turn radius than a regular tractor, but less than the ZTR.