im not sure where i should post this question but here it is. im looking into buying a tahoe for my family and me. we found a 2005 black Z71 with 116K for 15,000. the last chevy i had was an 89 s10 blazer 4.3 4x4 and i dont know much about the new motors or the newer gm`s at all. my question is, what problem spots do i need to check for or what do i need to look out for with these? also what is the best gas mileage yall have seen from these vehicles?