Terry, I am new to this Board & to eXmark, so let me tell you what I just bought yesterday. eXmark Lazer Hp - 52" Deck - 23HP Kawasaki - Model #LHP5223KA Serial # 279322 The machine has 501 Hours on it. I will be useing it for my personal Yard / Home use only. Can you also tell me when this Machine was Built & Sold? The Original Owner is not sure if he bought it in 2000 or 2001. I am doing a complete service on the Machine, & was wondering if the same weight Mobil 1 Oil that is used in the Hydro System, 15w50 Synthetic, would be OK in the Engine.