I run a 9500 and 9600 in beans, usually just run 1 combine in corn.  8 row on the 9600, 6 on the 95.  1000 ac total between both crops. They both have 6000 engine hours and are still reliable but won't last forever.  Plenty of capacity to get done on time. I would like to replace the 9600 and keep the 9500 for a backup, it's a creampuff.  I'm looking to update to a Hillco machine because we have a lot of HEL and loose some out the back even when slowing to 2mph on sidehills. I found a hillco 9670 with 5000 engine and 3200 sep hours. The HUR and big grain tank would be nice because we seldom unload on the go with our field shapes, and we are a 2 man show.  It is in use, I rode a round in corn, seemed to run good.  In the last 3 years it has had: feederhouse chain, hillco HD feederhouse faceplate, clean grain el chain, HUR vert and hor. auger, hor. auger tube, grain tank cross augers, concaves, threshing elements.   Engine was blowing coolant out the exhaust last year.  The head gasket was replaced and the head was surfaced.  Work was done in farm shop.  Owner states liner protrusion was correct.  Engine is code H008 which is supposed to be made after the liner issue problem was solved.  It has some blowby, about like my 9600 has had for many years.  A couple minutes after shutting it off the oil was at the add mark, so i'd say it uses some, owner claims not.  I do all of my own wrenching, including engine OH, so not afraid of high labor cost to keep an older machine running.  Is the cost to in frame a 9.0 liter reasonable?  My other option is to find a low hour 9610.  But then I lose the hillco and HUR and the low houred ones that I have seen are bringing stupid money.   I have never worked on or ran an STS.  Are there things other than regular wear items that wear out on them that make them non serviceable?  What value does the hillco kit add to a machine like this?  Other advice?  TIA