Quite a few years ago I had a Steiger ST251 that had the Fuller transmission in it. I also was under the impression it was simply a truck transmission. When it started jumping out of one gear I called Inland Truck in Kansas City to get it rebuilt. Talking to the mechanic he explained that although it was built in the same manner and shifted the same as the truck transmissions it was built much heavier in the shafts and bearings to take full load continously in the lower gears. He explained that truck transmissions don't spend much time in the lower gears and a tractor spends most of the time there, so the transmission is designed with that in mind. If you put a regular truck transmission in one it probably would not last long. I am not absoultely sure but I would suspect the Agcostar is the same situation - looks like a truck, shifts like a truck, but made for HD off road application. I don't recall what it cost for them to rebuild it but do remember the splines on one shaft was worn and I think one gear. Cost wasn't too bad - seems like $2500 or so - 10 years ago.

John