Great, I’m seriously considering trading in my rubicon for a diesel rubicon. Not buying it solely for mpgs but it’s be nice to know there is a considerable improvement over my 35s and 15.6mpg. Appreciate the check for oil change costs too!I still have my free oil changes to use, I am actually sitting at the dealership getting one now, I will for sure ask them what it costs for you, and I just got the tires on yesterday. They're going to recalibrate for the 37s since I don't have the Tazer yet so I'll keep you posted on that. I'm not going to Jeep Beach I'm leaving for Texas then Mexico on Monday so I will be able to dial in my MPGs on the trip. I will be at jeep fest in August though.