Just purchased a new to me JD 455. 1300 hours. Runs great. Think I did well on price. $3000.00 with JD 300, 2 decks and 54" 4way blade. Problem: 60" mower deck seems very weak. No jolt of PTO kicking in only slow ramp up to cutting RPM's. Deck loses RPM's when cutting and will actually stop...