We had the same problem . when you would also slow down the cylinder the cylinder would also speed up. if you shut combine off and wait few minutes you could lower reel and slow down cylinder. your dealer is high on parts we have a 96 9500 the solenoid was 417.00 . it took mechanic a while to figure out what was going on. the number one solenoid is having a slow leak. that is what tech support said from deere.