I don't know about the
M59 specifically, but on my Kubota there are 2 drain plugs in the oil pan. One on each side of the front drive shaft. I also know there are typo's in some of the different model Kubota owners manuals. Also, don't forget to pull the filter, since that can hold some oil as well.
Just make sure when you refill it, you don't dump in 9.9 quarts before you check to see if it is full. You don't want to over fill it.
I'm laughing here, and I'm with Achers on this one. If I hadn't rolled under the tractor to grease everything a few days ago, it would have been me and not you scratching my head and saying "Where in **** is the rest of the oil ??"
The infamous manual makes no mention of two drain plugs, just says "drain the oil".
I looked up, noticed the drive shaft tube tucked up safely away, and said to myself, "Self, whoever designed this thing had their ducks in a row, but I hope I never have to take the oil pan off... and come to think of it, how am I going to get the oil out of that side over there with only one drain plug over here, unless they... I slid over a couple more inches, and there it was !
Different design, I'll say that much. Since you have one drain plug right in front of you, why would you go looking for another one ?
I know what would have happened with me. I'd have happily drained the oil, replaced the one plug I removed, and added new oil. When it took two quarts less than expected, I would have muttered something about Japanese publishers and gone about my business with the old oil still mixed with new in the engine. Somewhere years down the road, I would have noticed the extra drain plug under all the mud and grime, the eyes would have narrowed a bit, and there would have been real swearing. And I'm willing to bet there are people on this forum that have read this thread and are now out looking under their tractors and shaking their heads after years of doing just that.
Congrats on the discovery, and I mean that. Most of us would never have realized there wasn't enough oil drained.
Chilly