I have the manual for my GX's and it does have a complete section on the tranny so I assume the earlier manuals will be the same. Really, when you look at what the manual covers they aren't as outrageous as they first seem. My manual has complete engine repair sections for the GX325's Kawi small block air cooled twin; for the GX335's Kawi big block ac twin and the GX345's Kawi water cooled twin. It was also indispensable for fixing the completely butchered up wiring harness and rebuilding a badly damaged tranny.