Chinda,

My best guess since you lost ALL gears, and you have no whine; I'm assuming fluid and filter are okay too?

I think the gear selector shaft broke, strip, or fell out?? The screw clamping the gear shaft could have broke, or unscrewed it self-out.

Okay, download the PDF on post 13 of this thread.

http://www.peachparts.com/shopforum/tech-help/321329-722-5-tear-down-side-start.html

Now, the transmission on the thread above is a 722.5, but I think you have 722.3xx or 722.4xx. The part is very similar in operation on your transmission.

Look on page seven:

The screw that can cause your problem is 333 if it malfunctions(lose or breaks)

The shaft, though hard to break, but not impossible to strip on the ends (330), yet 339 and 332 will con tribute to the problem on 330.

If 347 falls off 332 it is bad too.

Okay, lots of numbers! I'd drain the pan. Pull the filter off(unscrew the two screws). Locate the location where the shifter shaft plugs-in, and look next to the valve body. You may see the parts. I think this your problem since nothing works?

Martin