Called the dealer after5 days of not hearing from him,he states "waiting to hear from JD,if we have to eat the tires we will,I will contact you as soon as we hear from them,the replacement that come in also had cracked tires and we contacted JD about the issue" We told him we may bring it back for a refund,trade it for a D140 or look at another brand mower.I'm not sure about the B&S on the D140,the website states a KW but if not mistaken it is a JD branded B&S,it is $1899 which is alot cheaper than the X300.I wish Craftsman still used the Kohler Commands on their mowers like they did years ago,it is a great motor