for a 9770, used both during harvest, both are having power problems. Cutting 165 bu. corn, 16.5-17 moisture, could only run 3.5 mph without rpm's going under 2000 on the 9770 w/1293. The JD house doens't know what to do as "this is the first time they have seen this" and are pushing us to sign paperwork, but we are balking until they come up with a plan. The 9770 was completely serviced before delivery. 9770 has about 500 engine hrs. Has anyone else seen power problems w/9770 and if so, what did JD figure out? We used to cut 200 bu. corn w/9600 w/1243 head at 3 mph and had an '04 9760 and leased another '06 9760 in '07 cutting 200+ bu. corn with no power problems.